Another Disconnecting Doorbell

Any advice??My doorbell keeps disconnecting!!!If take the battery out put it back in then it works for approximately 5 hours and then disconnects again. I try and reconnect through the app but nothing.It used to always work, so it’s not the distance from the wifi (I have a ring camera further away that’s connected) I have reset my router but still nothing..Any ideas before this all ends up in the bin and I get something different.