Mazda CX5 Keyfob back fell off 2024 Carbon Turbo

Hello, I have the 2024 Cx5 Carbon Turbo and love it. Just noticed that the back to the Key Fob fell off at some point- don’t know how this happened. Luckily I have the key insert. Does anyone have any ideas how to replace the back part so that I am not held responsible by the dealer for a new whole key fob.
Additional 2 cents: this is the worst keyfob I have seen, too bulky. Thank you in advance.