You could try (512) 647-2000 and press "1" for tech support or "2" for billing.
I truly don't know if this will help or not, but couldn't hurt.
My impression is that Sipgate (a German company) is not emphasizing its US VoIP services right now.
They have had this notice posted for a LONG time now, for example:
Thank you for your interest in sipgate!
Due to the increased volume of new registrations within the last few weeks, we have unfortunately ran out of free numbers in your area and we are currently not able to offer you any alternative free phone number at the moment.
We have ordered a new batch of numbers which will be made available very soon but we're afraid we can't give you an exact time frame for this yet. Follow us on twitter and we will let you know when it will be possible to sign-up for an account with us again.
We apologize for the inconvenience caused by this.
They said "very soon".
It has been at least SEVERAL MONTHS!
It does NOT take that long to order numbers.
Further, their last meaningful Twitter post was a few months ago, ironically to a senior member of THIS forum. »twitter.com/sipgate
Something else to add is that their support is based in Europe. You likely will not get a response until the middle of the night our time. Be as specific as possible to avoid delays. Their support is not their strength. However a password reset should not be so difficult.
Do they e-mail you statements, or how does that work?
Look, you could make Outbound calls using lots of different providers....CallCentric, Voip.MS, CallWithUs, FlowRoute....
It's Inbound that's harder.
Did you have a phone number (DID) with Sipgate?
You might want to try to port it while you can....
Not trying to spread FUD but if you cannot contact support or billing for 1.5 weeks, if their website says "be back real soon" and leaves that there for several months, it strongly suggests that there is no one at home.
For that matter, didn't they send you some sort of notice and instructions when your credit card was declined?
Like the machinery of the Krell in the pioneering 1956 SF film "Forbidden Planet" things are on autopilot!