FSM mobile for windows shuts down with error on Windows 10

FSM mobile for windows no longer starts - or at least it starts and immediately shuts down again. It still happens after restarting the PC and also after uninstalling and re-installing the app.

I have this in the windows event log:

General:

Faulting application name: IFS.FSMW.Mobile.exe, version: 1.0.0.0, time stamp: 0x607711bb
Faulting module name: Windows.UI.Xaml.dll, version: 10.0.18362.1714, time stamp: 0xb81c2d40
Exception code: 0xc000027b
Fault offset: 0x0000000000712a30
Faulting process id: 0x768
Faulting application start time: 0x01d7a871a5c69bc5
Faulting application path: C:\Program Files\WindowsApps\IFS.IFSFSMMobile_6.5.7418.0_x64__4zvhwksmf3w4m\IFS.FSMW.Mobile.exe
Faulting module path: C:\Windows\System32\Windows.UI.Xaml.dll
Report Id: ccc74b68-f9ed-4a19-b8d0-f0a779669c48
Faulting package full name: IFS.IFSFSMMobile_6.5.7418.0_x64__4zvhwksmf3w4m
Faulting package-relative application ID: App

Details:

- System 
  - Provider 
   [ Name]  Application Error 
  - EventID 1000 
   [ Qualifiers]  0 
   Level 2 
   Task 100 
   Keywords 0x80000000000000 
  - TimeCreated 
   [ SystemTime]  2021-09-13T07:33:30.565114600Z 
   EventRecordID 93432 
   Channel Application 
   Computer N-KDE-01618.kme.intra 
   Security 

- EventData 
   IFS.FSMW.Mobile.exe 
   1.0.0.0 
   607711bb 
   Windows.UI.Xaml.dll 
   10.0.18362.1714 
   b81c2d40 
   c000027b 
   0000000000712a30 
   768 
   01d7a871a5c69bc5 
   C:\Program Files\WindowsApps\IFS.IFSFSMMobile_6.5.7418.0_x64__4zvhwksmf3w4m\IFS.FSMW.Mobile.exe 
   C:\Windows\System32\Windows.UI.Xaml.dll 
   ccc74b68-f9ed-4a19-b8d0-f0a779669c48 
   IFS.IFSFSMMobile_6.5.7418.0_x64__4zvhwksmf3w4m 
   App

Any ideas how to solve this?

Thanks very much!