Fès branch: the accounting account locks itself every 30 minutes

The MasterLinux branch in Fès has a single accountant, who uses the domain account compta.fes (domain masterlinux.lab). On Monday at 10:41, her password was changed (normal expiry, every 90 days).

Since then, the account locks itself about every 30 minutes. Support unlocked it four times yesterday and twice this morning: half an hour later, the lock is back. The accountant can no longer open the invoicing software or the share \\ml-fic-01.masterlinux.lab\compta: the branch's month-end closing is blocked.

The branch manager fears an attack (“someone is trying to guess her password”) and asks whether account lockout should be disabled.

You are the administrator, on the administration workstation ml-admin-01 (PowerShell with the ActiveDirectory module). Find where the bad passwords come from, remove the source, then unlock the account.