Fix mobile authentication on a mobile plugin

Hi, I need a php expert to fix an authentication issue on a mobile plugin for a website i'm working on. When you try to login through the mobile app it gives a couple of errors on the server and a blank page on the mobile page, I need this to be fixed. More details through PM. If this is fix more work will be available for the choosen one. Please serious bids. If you can work now and you have great understanding of english that would be great.