Temporary password not recognized after Migration Assistant from iMac to Mac mini

From late 2013 iMac running Catalina v 10.15.7 to new Mac Mini. Process worked without a hitch. Admin account OK same password. Temporary password for the two user accounts not recognised on either of them. Now locked out for over three hours on both for second time. New password is written down and photographed to confirm accuracy. No idea what to do when get my next chance to try. Any help appreciated. I am not a techy. Computers work by magic.

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