I'm sorry to hear that your friend is not able to send you money. If the error is not displaying any words, it may be that there's a technical issue, or it may be that the sender is missing some crucial information in the setup of the payment. If there's an actual error message, that may give a little more insight into what's happening.
You may also want to check your account just to make sure that there aren't any unresolved issues that need to be taken care of to receive payments.
I hope this helps!
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