Property Manager Fees: percent of rent collected or rent charged?

[Elizabeth Goff]

My original property manager was sold to a new PM about a year ago, and I have just recently signed the new contract, which come to find out says they will withhold "10% of rent charged".  They are now trying to charge me 10% for the past year for my non-paying tenant  (still waiting for covid funds). On the last tenant with covid funds they did not charge me until the rent was collected from the agency.  Basing it on rent charged does not give them any incentive to get the rent from the tenant, obivously.

Is there any other property manager out there charging as a percent of the rental charge, regardless of whether the rent is collected or not??