SOLVED only by reinstall of ioBroker at all,
was trying several things, starting with simple things
- atp update / atp upgrade /reboot
- checking and possible iobroker upgrade self (no effect everything was up to date)
- several restarts
--> no effects furtheron no connection nodered to mqttt even by changing ip-adress to localhost entry
by the way thanks for hints from TotallyInformation
Next steps single reinstall of - NodeRed
- MQTT Server
--> no changes same results
than next
**curl -sL https://iobroker.net/install.sh | bash -**
reinstall and reconfigure mqtt Server, NodeRed, reinstall all flows from backup
and now connection is possible, everything is working fine again ... the pitty finally I don't know what happen exactly but one thing nodered need to have a connection entry see picture
