Communication between Mobile and Nuki very slow

I have noticed that the communication between my phone and the Nuki is sometimes extremely sluggish.
When I approach the door, I often stand in front of my front door waiting for 10 to 15 seconds until the Nuki even starts to unlock the lock. Basically, 10 seconds is not long, but if I have to stare like an idiot at my door until it opens, and I would be faster if I took the key out of my pocket and unlocked it by hand, it kind of misses the point.

Same with the opener. I stand downstairs at the main entrance, select opener - open door and then I wait at least 20 seconds but often I have to press a second time to work. Every second try nothing works at all and i end opening the door by Hand.

The bridge is plugged into a socket about 10cm away from the Nuki.

Mobilephone: Samsung Galaxy S10 plus - Android 11

First part the same with my Mi Note 10 Lite with Android 11.
I use a fob and have connected the contacts of the push button to the control cabinet of my door cam, so I can open the dor via the app of the door cam, which is much faster