i have resolve this issue.
i followed this to fix the issue:
Could you check if you have this file in the pathway below?
"steamapps\common\Mount & Blade II Bannerlord\GUI\GauntletUI\spriteData.xml"
If so can you delete it and try again?
We don't use this xml anymore and if you have installed any mods prior this xml could be changed. The game still wants to use it if thats the case.
This should be deleted if the clean install workaround steps have been done appropriately. Do you remember seeing this file in the game folder after an uninstall?