Hier noch aus einem Log von einem anderen Shop, identisches Problem:
[2018-09-03 19:30:07] plugin.ERROR: PayPal: Could not create payment for plus payment wall due to a communication failure {“message”:“Client error response [url] https://api.paypal.com/v1/payments/payment [status code] 400 [reason phrase] Bad Request”,“payload”:"{“name”:“VALIDATION_ERROR”,“details”:[{“field”:“transactions.amount.details”,“issue”:“Currency amount must be non-negative number, may optionally contain exactly 2 decimal places separated by ‘.’, optional thousands separator ‘,’, limited to 7 digits before the decimal point and currency which is a valid ISO Currency Code”}],“message”:“Invalid request - see details”,“information_link”:"https://developer.paypal.com/docs/api/payments/#errors",“debug_id”:“eee0cd28a19d8”}"} {“uid”:“89d0e82”}