See this previous post, as this may be relevant to your issue:
In short, you can try the following:
- Make sure you External IP matches what you’re registering with SIPStations
- If you have more than one ISP, make sure your external IP matches your Asterisk settings
- Reset your token key in the SIPstation portal, as possible the settings may be wrong
If you’re a current SIPstation customer, I’m pretty sure you can call support and they will help you, as in my situation, they helped in about 20 mins.