Unable to purchase supporter pack

I am trying to buy a supporter pack but am receiving error 2205 from Xsolla but with PayPal and MasterCard:

2205: A valid User ID is required to complete this transaction. Please make sure you input your details correctly and try again. Otherwise, contact our customer support for further assistance at help.xsolla.com.

The Xsolla site does not document error 2205 but does have an entry for error 2207:

Error 2207 A valid user ID is required to complete this transaction. Please make sure you input your details correctly and try again. Otherwise, contact our customer support for further assistance at help.xsolla.com.

This error may appear if there are any technical issues on the game’s side. You can either check the game’s official website or contact us and we will try to help.

Can you assist? Just days before the account merge I was able to buy the Kalguuran support pack via PayPal with no issues.

Same here.
So, that will be Diablo IV then

Bump! - Same issue on my side. @GGG, please help! :)

Same here!

Same here :/ !

Issue resolved for me, the original poster.

Same