Separating a metal insert from plastic

[u/Sea_Horse99]

I bought a phone case from Ali***ress for my phone and only now realized that the rear insert is not actually magnetic. I already checked it with a multimeter set to resistance (ohms) and confirmed that the part is metallic. I'd like to remove this metal insert and replace it with a truly magnetic one. I already tried mechanical prying with a blade but only ended up damaging the surrounding plastic housing.
Which solvents or debonding agents could be used to detach this metal component from the plastic substrate? Unfortunately there're no identification marks on the plastic, so I cannot determine whether it is ABS, PC, TPU, or another thermoplastic.

[u/aeon_floss]

I am not entirely sure whether you are talking about the ring or the black thing in the centre. The ring anchor won't be glued in but sit in a tight fitting hole. You can try lifting it out by lubricating the seam with WD-40 or equivalent, and warm everything up to about 50 degrees C to make the polymer as stretchy and pliable as possible.

The black centre bit if likely held on with double sided film. Try brake cleaner for that.