My AirPod Max connects to my iPhone 16 but will not output audio

Hi there so I’ve recently just purchased a pair of AirPod Max’s and the first two days they were the dream I didn’t use them for a week but now when connected through Bluetooth they won’t play any sound such as YouTube/spotify/Netflix but I could hear an incoming phone call but then no further audio. I’ve tried selecting them in the airplay settings but it just loads and then nothing happens. Please help I bought them for traveling