Wondering if anyone has ever experienced this. Within my sage9 dev, I installed FacetWP, created a couple of Facets (type = select, data source = ACF fields) and placed the php in my custom taxonomy template. Page initially loads without error, once I make a selection from the select; URL is appended with variable, page refreshes with filtered results, then the page is redirected back to the originating URL, and it’s an infinite circular redirect until I invoke a refresh. I started with opening a ticket with FacetWP, but just wanted to see if anyone else has ever dealt with this.
You paid for FacetWP, so please try and get support there first. This forum is ran by volunteers.