[Help] How do I delete previous user Admin and other accounts?

[eflaat]

I bought a F-210 NAS and any time I try and access the NAS, it directs me to TOS4.1.X and there's no chance to register my own admin account, I think this was refurbished, I bought new, but I've tried every install guide and nothing. Tech support has been useless. I just want to use a NAS to watch movies anywhere in my home. Why is this so hard? Instead, it tells me to log in five different ways and nothing has worked so far. I have no way of finding out if this was a used model and what the old username password is or at least deleting it and having my own admin credentials.

I tried to add the NAS on TNAS for PC, it asks for a device ID, I don't have it since I can't log into the NAS, I tried through 'tnas.local' which doesn't connect and receives an error message. I tried setting up an account on TOS but there's no way possible and when I try and find the NAS through TNAS PC it always times out. This is frustrating. I hate this, I feel like I wasted $300, I want to throw this POS into the sun, will someone please help me as I'm sick and tired of living in this godforsaken world where there's no help from tech companies as they all have worthless AI or useless snail mail email contact that does nothing to help. For the love of all that's holy, will someone from this company prove their worth and just let me F*$&#* log into a NAS I paid money to access or is that too much to ask to buy something and have it actually work without having a PhD in software engineering?

This is where I'm stuck as Terra-Master is telling me what I already know, I don't have a user ID, but it's not letting me register one.

[TMzethar]

Based on your description, it is likely that the seller sold you the NAS along with the HDDs inside it, and the HDDs still have the system set up by the seller.
Please refer to this guide to reset the NAS system so you can set up your own account:
viewtopic.php?t=423
(Method B)