Can`t connect with one of my mobile Local

configuration:

Home Assistant 2023.9.2
Supervisor 2023.09.2
Operating System 10.5
Frontend version: 20230911.0 - latest

on a synology VM

Problem: I can no longer log in with my mobile : Error net::ERR_CONNECTION_REFUSED
I can log in with another or new mobile phone, but this is no problem

Tried: Deleted app including cache, restarted VM several times. Mobile deleted in HA, Backup restored in HA

All no results. It seems that I am able to connect but is denied.

it’s driving me crazy

can anyone help me? Thank you!

Yes, it works again. Solution that worked for me: I tried restarting the internet connection several times. also the VM. But the order changed. First start the Virtual machine and then reboot the internet

Maybe lucky shot.