What department should the property management company complain to when the security guard of the property management company hits the owner?

First of all, we must find out the reason for not letting in and whether the other party is reasonable (of course, hitting people is unreasonable).

Secondly, the property has no right to shut the owner out.

Thirdly, the property management company should be able to handle this matter well, but you should complain to the head office, not the project department (your residential property service center).

If the matter is serious, you can call the police or find the local housing authority.