Card failed to read

I recently purchased a Brother PE-180D embroidery machine
My sister has the Ultima that takes both floppys and cards but she has never used the card nor the digitizer
spent an afternoon playing with hers and had to have one, got a great deal on ebay but no card or reader...she said I can have herson permanent loan and when I get the digitizing down she has a few things in mind she would like done. heres my ? I downloaded 2 designs to the card and stitched away ...an entire chorus line of mini flamingos
and the a whole shoe store of flip flops
being a little bored I decided to download something else unto the card...I kept the flamingo and the flip flops and added some tulips , a moose and a frog but when I put the card into the machine it boldly displayed "THIS CARD CANNOT WORK. TURN OFF THE POWER AND CHANGE TO EMBROIDERY CARD" this is the only card I have so what went wrong ?
H E L P !!!!!