After upgrading TVS-882 to QTS 5.2.9.3499 admin account is locked - Please help!!!

Bought “preloved” TVS-882 fully populated with drives. It arived in the “reset” state and I was able to connect using MAC as password. First, I updated the firmware and apps. After a few days, wanted to continue with the setup but the unit locked me out. Apparently “admin” account is locked out by the latest OS if password is not changed. 3-second and 10-second reset doesn’t help. Hopefully good people here tell me how to recover from this nightmare! Please help!!!

Never use a 2nd hand NAS with drives, without sanitizing the drives first (it could have malware on it)

Take all the drives out and clear each drive (even SSD’s) externally (e.g. diskpart with “clean” flag) then.

Now go through NAS setup and start the NAS from scratch.
If your NAS does not have a cloudkey sticker, use QfinderPro to read out the NAS’s cloudkey before you put disks in.

Thank you, will do. Also, I did start the initial setup process and it gave me an opportunity to create a new account and thus I was able to unlock the admin account. Best!