Hey there @Wild88WolF! I would like to provide you with a short list of common issues to check first that will save us some time. After that is completed, if this issue still occurs, we will need to proceed through private channels. Please take the time to check and confirm the following:
Once these have all been successfully confirmed, please wait 48 hours in case there is a delay with any of the previous purchase attempts. After 48 hours have passed, if you are still unable to complete the purchase, please log in to our support site and submit a new ticket for this issue. One of our agents will review everything and then follow up with you directly. To save time, you can also link to this discussion board topic in your ticket description, and they'll be able to review the information here as well. 
This is likely what's causing the issue then @Wild88WolF,
If the Steam, Ubisoft Connect, and actual location do not match, this typically causes payments to fail. My apologies for the inconvenience and frustration of this and let me know if you have any other questions.
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