Motherboard Serial Incorrect message during registration

[Jay1]

System: Window 64bit
Battery or AC: AC
Model: Asus Tuf Gaming B550=plus
Frequency of occurrence: Frequent
Reset OS: yes
Screenshot or video:
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Detailed description：Unable to register Motherboard serial number on MyAsus account says "serial number incorrect"

[Blake_ASUS]

Dear both,
Please check your PM and refer to below link

How to find product Serial Number

Thank you.

[nvidiajunkie]

Same issue here.  I purchased mine o/a 10 May 21 and entered the serial number I got from the bios using this command string, which also matched what AI Suite's System Info showed, and yet still got this response trying to register:  serial number incorrect.