Doorbell plus not picking up motion

We have a new battery doorbell plus along with a chime pro. We’ve had it a few weeks but it only seems to pick up 8 out of 10 motion events. People can come right to the front door, we can come and go and it won’t record anything. It’s got an RSSI of 61 (it’s literally the other side of the chime pro) and is mounted at the recommended height (I want to say 1.2m) with a view directly down the pathway to the street. It has the sensitivity turned all the way up (we’ve tried different settings), motion zones set up for most of the field of view and there is no schedule or modes enabled. We also have a floodlight cam which does pick up the motion. If someone rings the bell then this all works ok and is recorded but just motions is missed most of the time. It’s not picking up anything before the motion so it’s not that it’s on a ‘cool down’ etc. any recommendations on what to do please?