UK Car Repair: timing belts vauxhall vectra, timing belts, timing belt

Question
I had timing belt replaced , timing belt cover was not refitted, after approx 1800 miles my timing belt went again, would the fact that cover was not replaced affect this

Answer
It is possible something could have gotte in and fouled the belt.  I would check all the pulleys, perhaps one is damaged. Some pulleys have a retaining ridge that prevents the belt from moving, does yours? See howe easy the engine turns something might be unusually tight.