Getting error on product info page

[narenbambhaniya]

[28-Jun-2025 08:01:33 UTC] Request URI: /index.php?main_page=product_info&cPath=21&products_id=29, IP address: 49.36.83.131, Language id 43
#0 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(206): zen_debug_error_handler()
#1 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/classes/observers/auto.structured_data.php(62): include('/home1/dev2nlin...')
#2 /home1/dev2nlinksolutio/public_html/includes/classes/traits/NotifierManager.php(106): zcObserverStructuredData->notify_html_head_end()
#3 /home1/dev2nlinksolutio/public_html/includes/templates/winchester_responsive/common/html_header.php(179): base->notify()
#4 /home1/dev2nlinksolutio/public_html/index.php(43): require('/home1/dev2nlin...')
--> PHP Warning: Undefined array key "lang" in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php on line 206.

[28-Jun-2025 08:01:33 UTC] Request URI: /index.php?main_page=product_info&cPath=21&products_id=29, IP address: 49.36.83.131, Language id 43
#0 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(206): zen_debug_error_handler()
#1 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/classes/observers/auto.structured_data.php(62): include('/home1/dev2nlin...')
#2 /home1/dev2nlinksolutio/public_html/includes/classes/traits/NotifierManager.php(106): zcObserverStructuredData->notify_html_head_end()
#3 /home1/dev2nlinksolutio/public_html/includes/templates/winchester_responsive/common/html_header.php(179): base->notify()
#4 /home1/dev2nlinksolutio/public_html/index.php(43): require('/home1/dev2nlin...')
--> PHP Warning: Trying to access array offset on null in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php on line 206.

[28-Jun-2025 08:01:33 UTC] Request URI: /index.php?main_page=product_info&cPath=21&products_id=29, IP address: 49.36.83.131, Language id 43
#0 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(206): zen_debug_error_handler()
#1 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/classes/observers/auto.structured_data.php(62): include('/home1/dev2nlin...')
#2 /home1/dev2nlinksolutio/public_html/includes/classes/traits/NotifierManager.php(106): zcObserverStructuredData->notify_html_head_end()
#3 /home1/dev2nlinksolutio/public_html/includes/templates/winchester_responsive/common/html_header.php(179): base->notify()
#4 /home1/dev2nlinksolutio/public_html/index.php(43): require('/home1/dev2nlin...')
--> PHP Warning: Trying to access array offset on null in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php on line 206.

[28-Jun-2025 08:01:33 UTC] PHP Fatal error: Uncaught TypeError: trim(): Argument #1 ($string) must be of type string, null given in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php:90
Stack trace:
#0 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(90): trim(NULL)
#1 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(206): sdata_prepare_string(NULL)
#2 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/classes/observers/auto.structured_data.php(62): include('/home1/dev2nlin...')
#3 /home1/dev2nlinksolutio/public_html/includes/classes/traits/NotifierManager.php(106): zcObserverStructuredData->notify_html_head_end(Object(notifier), 'NOTIFY_HTML_HEA...', 'product_info', NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)
#4 /home1/dev2nlinksolutio/public_html/includes/templates/winchester_responsive/common/html_header.php(179): base->notify('NOTIFY_HTML_HEA...', 'product_info')
#5 /home1/dev2nlinksolutio/public_html/index.php(43): require('/home1/dev2nlin...')
#6 {main}
thrown in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php on line 90

[28-Jun-2025 08:01:33 UTC] Request URI: /index.php?main_page=product_info&cPath=21&products_id=29, IP address: 49.36.83.131
--> PHP Fatal error: Uncaught TypeError: trim(): Argument #1 ($string) must be of type string, null given in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php:90
Stack trace:
#0 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(90): trim(NULL)
#1 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(206): sdata_prepare_string(NULL)
#2 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/classes/observers/auto.structured_data.php(62): include('/home1/dev2nlin...')
#3 /home1/dev2nlinksolutio/public_html/includes/classes/traits/NotifierManager.php(106): zcObserverStructuredData->notify_html_head_end(Object(notifier), 'NOTIFY_HTML_HEA...', 'product_info', NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)
#4 /home1/dev2nlinksolutio/public_html/includes/templates/winchester_responsive/common/html_header.php(179): base->notify('NOTIFY_HTML_HEA...', 'product_info')
#5 /home1/dev2nlinksolutio/public_html/index.php(43): require('/home1/dev2nlin...')
#6 {main}
thrown in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php on line 90.

[28-Jun-2025 08:01:33 UTC] Request URI: /index.php?main_page=product_info&cPath=21&products_id=29, IP address: 49.36.83.131
--> PHP Fatal error: Uncaught TypeError: trim(): Argument #1 ($string) must be of type string, null given in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php:90
Stack trace:
#0 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(90): trim(NULL)
#1 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php(206): sdata_prepare_string(NULL)
#2 /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/classes/observers/auto.structured_data.php(62): include('/home1/dev2nlin...')
#3 /home1/dev2nlinksolutio/public_html/includes/classes/traits/NotifierManager.php(106): zcObserverStructuredData->notify_html_head_end(Object(notifier), 'NOTIFY_HTML_HEA...', 'product_info', NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)
#4 /home1/dev2nlinksolutio/public_html/includes/templates/winchester_responsive/common/html_header.php(179): base->notify('NOTIFY_HTML_HEA...', 'product_info')
#5 /home1/dev2nlinksolutio/public_html/index.php(43): require('/home1/dev2nlin...')
#6 {main}
thrown in /home1/dev2nlinksolutio/public_html/zc_plugins/StructuredData/v2.0.0/catalog/includes/templates/default/jscript/structured_data_jscript.php on line 90.

[torvista]

In what version of Zen Cart is this?

[narenbambhaniya]

Its zencart 2.1.0

[narenbambhaniya]

Note : Its multilanguage store

[torvista]

I don't see why the lang element is missing at 206.
There should be the $product_info object containing:

You can add this before 206 to see what $product_info contains:
echo '<pre>'; print_r($product_info);echo '</pre>';