I got a form I-797C, Notice Type ''Rejection Notice''

I have submitted status change and downgrade from eb2 to eb3 in Nov 2020. I got form I-797 for my child which says NoticeType- “Rejection Notice” and has below contents and it does not have receipt number.

Recently, you submitted an application for immigration benefits. That form was submitted with an extra remittance this is not required to process your application. Your payment is being returned to you with this notice. No additional action by you is required at this time.

Can you help me understand it? Is application rejected or it is just over payment refund notice.

It sounds like an over payment issue and not rejection.