Synology NAS - after migration to new NAS

I’ll try to make brief but I need to set up - I had a Synology NAS DS-718+. I got an addnl NAS that I just migrate the info from my first NAS.

Now I am using my first NAS for my daughter’s business and mainly for Surveillance.

The problem is that I can’t seem to get Tailscale to activate on both my new NAS anbd my old NAS at the same time. To activate one or the other I have to SSH into the NAS and do the sudo tailscale up command. However, when I activate the old NAS (for eample) called xxxxNAS it thanks me for activating the new NAS name xxxx920NAS. I think that there must be similar info in the file that is on the old NAS that somehow got copied over tot he new NAS so that tailscale isn’trecognizing the deivices as differnt devices. Initially my concern was that they were on the same network but now they are actually in differnt parts of the country but still has same issue.
How can I complette delete all old tailscale info so I can get both going at the same time?