Locked out - suddenly the phone requires a PIN after a restart

**I recently flashed eOS onto a Samsung S7 edge and it was working well.

I then sent it to a repair person to replace the battery.

When I got home the phone is now asking for a PIN to unlock it. I don’t remember doing this (only biometrics). So I’m locked out of the phone!

How do I get past this?
(I don’t mind doing a full reset, since it was a fresh install and there’s not data on there yet - but I don’t know how to do that without getting into the phone first)**

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