WBS Rent increased 2 years in a row

[Berlin_Insomniac]

does anyone know if it is allowed for a landlord to raise the rent two years running? for further context, this is a 100WBS contract, subsidized for people who cannot afford the market rates.

if you dont know about this matter specifically, where can i look up for rules surrounding home rental?

Thanks in advance

[PandaMunich]

Are you sure it was the rent that was increased?
Or did they maybe only increase your Nebenkostenvorauszahlung, i.e. your monthly prepayment towards heating, warm water, janitor and so on?