Tamnia,

it seems our paths at this time are going in sync.

I have been going through the exact same case. I am Canadian btw.. I got an offer to work in Doha .. and as you did, they only ask for my passport copy ..and said it will be fine ..
and two days again they said (The sponsor told them that I am blacklisted or rejected for any Kind of Visa )
I have never been IN Qatar; I insisted they try to check for mistakes or name similarities *(am or arabic origin) they took another three days and came back today with same answer..

I dont know how this works; but certainley something is not quite rigth.. I.e. people lifes are not jokes..
I ahve a family to provide to, and when they got me the contract here, they asked me to join ASAP so I had to resign from my work .. and now .. ??? yes you guessed .. good luck chuck !

I dont think anyone here can help you although alot of nice folks around they try to make it easier on you, but no one is feeling you but yourself. .. I suggest if you have means to talk to a Qatari embassy in your country then do .. this is what I am going to try now.

good luck.