No Apple Watch notifications when charging

I have an Apple Watch 7 and, when charging at night using a Belkin Charge boost 3-in-1 no notifications appear on the watch, as I want during the night.

the phone is on silent. In watch app notifications are set to custom to allow notifications for eg messages.

neither the Watch or phone is off via focus. I read somewhere that you should turn off wrist detection, but that disables the security so not preferable

all works great when watch on wrist. As soon as you put it on charge on the belkin it seems like it puts the Watch to sleep and no notifications show up. I have tried it with bedside mode on and off.

I read somewhere that the theses sort of third party products put the Watch to sleep when charging.

Any ideas or advice please?

Thanks