Hello sir,
Your feedback has been greatly appreciated. Due to a conflict with that theme, you have faced that problem and we apologize for that. Our team will work as fast as possible to resolve the issue. However, this error will not occur if you use Gutenberg blocks to insert the TOC on every page instead of auto-inserting the TOC.
It is a pleasure to have a customer like you. We hope to come up with a solution as soon as possible and notify you so that you can use the plugin again.
Thanks
Boomdevs