Problem solved. Windows 11 was offering an optional update for BIOS 1.13. Case closed 
Hi, My XPS 9510 has BIOS 1.12. When i check drivers on Dell Product support I see there is an update 1.13 available. Also for my Dell XPS.  I don't want to install this BIOS manually. I prefer to install this update with Dell Update 4.21 (which worked fine with prior BIOS updates). However the new BIOS update has a publication date 14 september. Normally such an update appears within a week in Dell Update. But not this time. Also, SupportAssist doesn't show this update either. I allready uninstalled Dell Update and SupportAssist but still there is no BIOS update presented.Anyone an idea how to solve this?Kind regards, Wilco
Dell Update 4.2.1 is not installing BIOS 1.13.0