A hypothetical person lives in California, USA and signed a paper lease. The landlord returned the signed lease to the tenant in 10 days. The lease contains the exact schedule for monthly rent payments.
January : $ xxxx.xx February : $ xxxx.xx ... December : $ xxxx.xx
The landlord made a mistake in the payment schedule for one month resulting in a one time 20% rent decrease in April.
The tenant moved in and started executing the payment plan specified in the lease.
Eventually the landlord caught the error and tried to collect the remaining balance of 20% for that month.
Does the landlord have a legal standing to claim a typo in the signed lease and try to collect the remaining 20% for March?