I’ve read multiple articles on this topic, but I’m not completely sure I understand. I sent my cancellation request through email but do I have follow up with a letter to Germany? Seems a bit excessive.
As you can see, the purchasing details clearly state that you can use email. Quote: "To cancel the contract, please send an email stating your customer number to: infoservice@magix.net". I do not see any mention that you'd need to confirm with a follow-up letter. Admittedly, OTOH the support article may give you that idea by not making it clear that the two ways are options to make the cancellation in writing. Note that your request may not have been processed yet if you sent it during the weekend or late last week.
You're asking for a refund for software that costs less than $20/month? Software that has a free demo out there for you to test it before you purchased it?