Hi aga2442,
Thanks for reaching out.
Advanced Ads supports PHP 8 and you should be able to show ads in your theme. I recommend starting with the basic plugin and a dummy ad to ensure the general ad injection is working as expected.
After this, I suggest activating and testing the Advanced Ads Pro add-on and it’s functionalities one by one to see what exactly is not working. Looking for error messages in your browsers’ console or PHP log files might help to understand what is not working in particular.
Due to the theme change, the elements on your website might also have changed. I recommend re-creating your previous placements, like the Custom Position placement or sidebars, if used, so it can work as expected.
Version 2.9 is about two years old by now, I might not say if there were changes on WordPress, PHP, and the add-on until now braking some functionalities. Following the steps above should give a better idea on what is not working exactly.
Kindly note that this forum is only for the support of the free Advanced Ads plugin, which is also hosted here. Questions about the paid add-ons can be addressed to our customer support.
Best regards,
Henning