It seems that you may be receiving multiple invoices due to the changes in billing periods for Microsoft 365 subscriptions. When a subscription renews, you might receive two invoices in the same month: one for the previous term and another for the upcoming term. This is especially true if your subscription was set to renew around the time of your inquiries.
Regarding your request to speak with a Microsoft representative, you can contact Microsoft support for assistance with your billing inquiries. They will be able to provide you with detailed information about your invoices and any other concerns you may have.
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