Yeah, it is OK. I found a Cisco doc last year that recommended 2 VTP servers for redundancy. This was mainly for CatOS based switches, because CatOS VTP clients do not store any vlan info at all ...

They really should put into the log which port the BPDU was received on. I would bet, if you have any wifi equipment connected to that switch, that is the source of the issue.

5 – VTP Domains. Organizations often ... It is a best practice to use PortFast with BPDU-Guard so that it defensively shuts down the port if a BPDU is received on that interface.