It sounds like you have a bad pm if they are ignoring when you are trying to contact them. I would wonder if the previous owner owed them money and they dont believe ownership changed. A lot of times it is best if the existing pm is the listing agent so they can negate this along with tenant communications. Did you receive security deposits with interest and pro rata rent for the month at settlement?
The pm could also be very unethical. They should atleast be communicating with you. It would be helpful if you had your settlement papers. When sdat and city taxes updates there will be no question though that could take months.
A lot of the better pms void this by only managing in the better parts of Baltimore city or the suburbs. There they have a much higher likelihood to get tenants who will pay not to mention respect the property and make things easier for everyone. If you are in a lower asset class things can go the other way. A lot of voucher tenants actually can afford to not live in the worst parts of Baltimore but won't live in the best either. Thus you might be able to find someone. As things get more difficult more and more and just staying higher end. If you go too low I would either recommend self managing or liquidate it. The best lower end property landlords self manage. The best way to look at things is the amount of hastle and money the pm will make. In low end properties they dont make enough and they also take on considerably more risk.
If you can share the address it could answer some questions.