in-app purchase in udemy double charged my apple iTunes card but udemy only got paid 1 time?

in-app purchase in udemy issues with it going thru had $ on my apple iTunes card account in my account. I kept getting messages that it payment wasn't going thru to try later. So I try again between my iPad pro and my iPhone xs max. Now I have been billed twice to my apple itunes card but on the udemy website shows it has been paid 1 time and show 1 receipt there. I try on apple website to report it several times and each time it rejects it every time! why! Is there a chat or email that I can report it that way. I have try to report it by clicking on the report it from the page of the receipt and it opens and lets me submit but won't accept it. ugh so frustrated. I even contacted udemy if I purchase directly via website it would be no problem getting refunded but because it was thru the apple app that is where the issue have to get apple to refunded it but how if we can't get them to accept the form?