Auto starts when car Bluetooth is on....

How in the ever living shit do I turn this "feature" off? Every single time I get in my truck, & turn my phones Bluetooth on, the instant it connects to my truck it starts playing some rogan episode I halfway listened to 2 years ago..... it supersedes ANY other program I'm wanting to use. I mainly use Amazon music, so every time I have to wait for Spotify to load and manually close it then open my preferred music app....