Check your state landlord tenant law on rent increases for month-to-month tenancies. Unless the state or local law forbids rent increases without 60 day notice or limits the % increase, you have to pay the increased rent or move. Make sure landlord gave you adequate notice. Landlord has essentially terminated your old month-to-month agreement and is giving you the terms of a new agreement. If state law requires landlord to give 30 days notice to terminate the agreement, and landlord gave you less than 30 days notice of the rent increase, the notice is not effective until next month.
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This is not legal advice and you are not my client. Double check everything with your own attorney and your state's laws.