So I am using multiple resources in AWS. The charges make sense for most services. however, at every first day of the month, I am getting charged more than I should.
For example; charges for services such as, Aws active directory service, EC2, step function, the elastic search is normal throughout the day. as I can drill down daily charges for these services. but every first day of the month, AWS charging more than what it usually charges. For example; if the average charge for EC2 instances for the day is $5 then at every 1st date(let's say 1st January) of the month, the charges end up for EC2 instance somewhere around $15 and again on 2nd January charges would back normal to $5.
also, for the AWS Contact center telecommunication service, my usual charges for the day would be around $10. but again on the first day of the month, I am getting charged around $150. This is way more than what it charges on regular days.
I don't get this behavior. is it done on purpose or am I missing something?
Thanks.