Sorry to point you towards a very long thread following this issue with Fairphone 3, 4 & 5 devices but haven’t managed to work my way completely down it yet. Seemed to have been some success with Phonak but not sure about Oticon. https://forum.fairphone.com/t/fp3-fp4-fp5-hearing-aids-and-direct-streaming/78511
Unfortunately was one of the reasons I had to look for another device after FP3 to utilise my Phonak ones.