JustVoip - www.justvoip.com

I have my justvoip account and an account credit of $ 23.12 and 49 free days left. But when I try to make a call, it says, "The other party ended the call due to an unknown error." This has been so for the past two months. I sent e-mail complaint to the Justvoip service team, but the error is not corrected. If the company cannot rectify the error, I expect the money to be put back into my account.