Apple Watch notifications get lost forever while it is charging

My main use for my Apple Watch 4 Cellular is receiving push notification without having to carry the iPhone with me (I use another phone). Since the notifications of third party apps are dispatched only if the iPhone is connected to the Internet, I am currently leaving the iPhone always plugged in the power lane and connected to a stable Wi-Fi and cellular network (not in my place, since my Wi-Fi is not stable and I can't change it).

All seems to work fine, BUT when I put the watch to charge during the night, then I miss all the notifications. That is, when in the morning I pickup the watch, all the notifications received during the night remain on the phone and are not dispatched to the watch. This is a big problem for me. Is there any way to overcome this? At the very worst case I will have to try moving to Android, but I really hope to be able to remain within Apple products.

More details:

• I am not using Theater Mode, neither Do Not Disturb.
• All the apps are enabled to receive notifications both in the iPhone and Apple Watch.
• The iPhone is constantly locked.
• As stated, we can assume the iPhone is constantly connected to the Internet.
• In my room there is no stable connection, so the watch is maybe not always connected to the Internet, but after a while it reconnects. Anyway, I have done some experiments and even with a stable connection to the watch no notifications is recovered after picking it up from the charging station.

Thanks for the help