SIP2SIP

Hi,

There is nothing wrong with your account, UDP should also work.

The problem is in the the number pattern you try to dial. The country code is missing. Please try it with the country code prepended, either by using + or 00

Thank you for the info. I haven't used SIP phones for years and remember this was an issue years ago but aren't systems designed to "assume" it would be called locally. I know it goes the same for businesses using physical IP phones as well.
Is this something that I can set somewhere myself?

Unfortunately you can't set this yourself. It does work like you say. It assumes the number is local.

Since the servers are based in The Netherlands, it assumes they are +31 numbers and tries to call +31...

OK. But I am also trialling the Sipgate service that is based in Germany but they do have a setting that would cover this
https://basichelp.sipgate.co.uk/hc/en-gb/articles/115000648509-Automatic-Area-Code
Would you consider having something like this also?