Called back and it had a message basically saying "this is an unattended service for your information. if you're calling about a missed call, it originated from this number. it may be from a charity you support, or one who wants to ask for your support... blah blah. It gives an email you can contact to ask not to get calls any more, but I couldn't understand what the woman in the message said, so I'll just be blocking the number from now on.

I called back number 0491 051 862 reached voice mail but did not say for what company.