Poor service

I am not sure where to begin as I am highly disappointed with the recent service. When it started everything was fine till 4 months back, whenever I try to make purchase I get declined but I can still see my balance that's so disappointing and embarrassing. Every time message is sent, I then receive a response that they are waiting feedback of when the system will be working. There's a technical fault somewhere in the system (NOT OYI) which is in control. I feel so lost, if they don't even know what's the cause and fails to fix it on time, I might wait forever to get my money back. If they can no longer operate or fulfil their promise, why not refund customers?