Edit: Solved.
Remove and re-add the P1 dongle.
With this script it was not a PITA to fix all flows 
Hi Jeroen,
Since today 15:00h my P1 dongle lost its connection with Homey and won’t connect anymore.
First this error:
.
I’ve checked it’s still on IP …15 :
Just now, the error changed to Forbidden.
I restarted the app, Homey & p1 dongle.
Installing app v2.1.21 over v2.1.16 did not change things.
It’s continuous in use for over a year w/o any issue.
The mobile ‘Energy’ app is still connected and up-to-date.
My simple Experia-v10 router is 96hrs online (so no recent changes I assume), I also didn’t change anything in my setup.
Other 2.4GHz devices directly connected to Homey (HomeAssistant, Marantz, LG webOS, Onvif) have no issues.
I can’t think of anything to try.
Hopefully there’s some info in the diag. reports
1st: eb317b90-3859-4b4f-a868-902d43d520b9
2nd: ef612ed5-7380-433e-8fd2-a1de54897415
Homey firmware v7.4.2;
v7.4.3 since 18:44h today, June 23rd.
No hurries! I can live without it 
