My MA was in theology and I was admitted to a philosophy PhD program, although my undergrad was in philosophy, so I at least had that. It’s difficult but doable. I chose to use a writing sample that was not related to religion in any way in order to demonstrate my interest in philosophy proper as well as to show I had a firm handle on philosophy. I also chose not to advertise the fact that my MA was in theology. Of course my CV listed my MA in theology, but I never mentioned theology in my SoP; I just referred to my graduate work or my MA. And of course I was strategic about what programs I applied to. I’d recommend Notre Dame, Georgetown, Fordham, Baylor, Notre Dame, Boston College, Saint Louis University, and Villanova as programs friendly to philosophy of religions, but others are as well. I have friends doing philosophy of religion at places like UT-Austin and USC, but they did MAs in philosophy, so that makes a difference.
Hopefully this helps. My bottom line advice is to be strategic about your application and where you apply, but also don’t limit yourself. You never know what might happen.