For several days I was unable to receive incomming calls with EcallPlus Oxygen GSM. The sender would get the 'check the number and dial again' message. After spending nearly an hour on the phone with customer service, during which time my account was suspended and reinstated several times, the problem was traced to a bad routing number and fixed. That was the start of my prolems with EcallPlus. They voluntarily credited my account with $2 worth of airtime (in addition to the time already in the account). The next day, all the funds dissappeared from my account! Complaint to customer service first brought the response that the time had expired, which was simply not true. Futher complaint resulted in the $2 be recredited to my account, but EcallPlus claimed they had no record of any other funds ever being deposited to the account. I asked to speak to a supervisor, and was transfered by customer service. After about 15 minutes on hold I was disconnected. Email correspondence goes unanswered. I recommed you deal with Pharos International (www.pharosint.com/index.html) instead of EcallPlus. The airtime they sell will work on the EcallPlus system. And, just in case, be sure to save all the billing information.