Hello,
Please, check now !
We have found the reason of the issue and already fixed it globally so it will be included in next XStore AMP plugin update.
The issue was that you don’t use brands functionality but we had a condition that checks only if to show brands on shop ( https://prnt.sc/P-6LDi0GAh6X ) but not if brands are enabled ( https://prnt.sc/lWwGsqapBH0f )
Fix is located in plugins/xstore-amp/includes/actions/filters.php
Regards