Thanks for your message. The indexing is already correct in the NTVMR for P125. It does not contain 1 Peter 5.
I checked some passages in 1 Peter 2 in the ECM, but did not find any mistakes with P125 either.
Perhaps you’re confusing this with another manuscript?
This is possibly a confusion for Uncial 0206 (feature of a recent blog post on ETC by Tommy Wasserman - link), which discusses this very variant.
The verso of the parchment page was missing its Scripture tagging (fixed now). Could do with an up-to-date transcription :)