Hi ervane,
Thanks for letting us know the update. It may happen due to the conflict also. Can you please check for plugin conflicts by following this:
Plugin conflict check: Often, we see problems occur in combination with another plugin or theme. The fastest way to rule out any conflict is to temporarily deactivate all the plugins except the Image Gallery Block plugin. Simply go to your WordPress Dashboard and navigate to wp-admin => Plugins, and then deactivate other plugins.
After deactivating all plugins, check if the issue still persists. If the issue goes away, then a plugin conflict is likely.
Enable plugins one by one: Reactivate your plugins one by one, checking the website after each activation to see if the issue reappears. This will help you identify the plugins causing the conflict.
Besides, you can switch to a different theme like Astra, Flexia, or Twenty Twenty Three. And, check back as well.
Let me know how it goes.
Thank you!