It is hard for me to comment since I do not have your specific policy details. However, based on the information you provided, it appears that other factors may be involved. Your rates would not necessarily increase because you simply missed a monthly payment. It is possible that if it were for your renewal premium that you may have lost a discount. Or, if you missed a payment then it is possible that your policy balance was recalculated into a smaller number of remaining payments results in a different payment amount. You should contact your agent for more details regarding your policy.
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