Double check your management agreement.
There is typically verbiage that states the owner must notify the management company a specific number of days out from the end of the current lease term to discuss any desired changes whether its for price increases, non-renewals, renewals, etc......The number of days out correspond with the notification dates to tenants based on state law.
The verbiage probably also adds that if the owner does not notify the management company prior to the certain number of days out, it is agreed by all parties that the management company will renew the lease or release if tenant is vacating.
As far as a rent increase, landlords/owners should verify prior to hiring a management company of what the escalation clause is for each renewal.
I bet the management company followed the agreement but an extra email to our clients always avoids an aggravating situation like this.
Good news is that you do not have a vacancy and all the added costs because of it.