Hello there,
Let’s see how we can help.
Please first deauthorize Optin Cat from the list of authorized apps in Aweber’s account area then enter a new code again in the Auth Code field. Then check if the issue persists.
If it still has the same issue, then there might be conflict in between Optin Cat and your currently active theme or other active plugins since we don’t have other reports from other users and is most likely an issue unique to your installation.
To search for conflicts, please follow these steps.
1. First please deactivate all plugins except Optin Cat and see if the issue persists.
2. If the issue is resolved, reactivate your plugins one by one to see if the issue returns.
3. If no conflict is found among your plugins, try reverting to a default WP theme like ‘Twenty Sixteen’, or ‘Twenty Seventeen’, and see if the issue is resolved.
Head here for detailed instructions:
https://fatcatapps.com/knowledge-base/search-for-conflicts/
If you find a conflict with a plugin or theme, let us know what it was so that we can release a fix if it’s a popular one. Also, try to contact the contact the author of the theme or the plugin to see if they can fix it.
Thanks.