if you don't get any answers to your issues/errors/problems/questions in the "Plesk - related forums", it might be, that your issues/errors/problems/questions has absolut nothing to do with Plesk or it's compoents at all. Such threads should as well being created at =>Open Topics
Due to the fact, that your described issue is only related to "PrestaShop", it would be a good idea to open a thread at for example: =>https://www.prestashop.com/forums/