[ad_1]
If you check the console in the browser you’ll see the error:
Div ID passed to googletag.display() does not match any defined slots: div-gpt-ad-1671699861624-0.
You are using ad with this ID in the body part. This code runs immediately after the page is loaded. When you insert the code which defines this ID in the header (block 22), this code will be inserted after the ad code using this ID has already run. Therefore, you will get this error and no ad will be displayed.
Your approach is not suitable for this kind of ads. Ad Inserter supports few features for ads that need separate header code:
https://adinserter.pro/documentation/ad-manager-ads