Windows 10: UEFI Boot

Following a Windows 10 updateto version 2004 on 18thAugust 2020, my PC goes into a boot loop, I can get out of it by pressing F12 and selecting Windows Boot Manager rather than the default UEFI partition 1 on a Kingston SSD. The PC then boots and runs normally.
I would like to repair/restore the UEFI partition - I have tried the startup repair using ALT-F10 but this is unable to fix it. I have also looked at the SSD and partition 1 shows as healthy.
Any help would be much appreciated.
PC is Acer Aspire XC-885.

:)

 

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