I looked at the requests going out, and it seems they are syntactically OK.
Here is what is sent out for the failing request:
<?xml version="1.0" encoding="UTF-8"?><soapenv:Envelope xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"><soapenv:Body><cancel xmlns="Platnosci.Payments"><posId xsi:type="xsd:int">3434</posId><sessionId>dsf</sessionId><ts>sadsfsdf</ts><sig>serw342354234sdfsdf</sig></cancel></soapenv:Body></soapenv:Envelope>
The question is whether this is a valid request to https://www.platnosci.pl/paygw/webapi/Payments, which is difficult for me to tell, because www.platnosci.pl is in Polish.
I suggest one of the following:
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