What *exactly* does the lease say? Do you have to give them notice 30 days before the lease expires that you won't renew it? Does the notice have to be in writing? Since the written lease contains its own notice of termination on 1/31, you may not need to give notice. It could just be that the lease terms will continue to be in effect after 1/31 if they stay & you collect rent.
Hint: don't accept Feb rent. Just sue them for unlawful detainer (holding over) as soon as you can. Probably on 2/5.
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