The ordering process in Ubercart is glitching.

Please help me with advice

when clicking the "Add to Cart" button for some products, the following appears on the screen

[{"command":"settings","settings":{"basePath":"\/site_mstore\/drupal7_mstore\/","pathPrefix":"","ajaxPageState":{"theme":"mstore","theme_token":"wSmz3u_e17EHMqoVuq_DOAr5oqq6fUL5w-UrLIeNqaQ"},"colorbox":{"opacity":"0.85","current":"{current} of {total}","previous":"\u00ab Previous","next":"Next \u00bb","close":"Close","maxWidth":"98%","maxHeight":"98%","fixed":true}},"merge":true}]

I have no idea where to look for the problem. Please advise

while some products are added to the cart without any issues

I also tried deleting the ubercart module and reinstalling it. I also tried disabling all the JavaScripts I wrote. It didn't help