Took my 2007 Chevy Avalanche that only has 57 thou...

Took my 2007 Chevy Avalanche that only has 57 thousand mile in on Thursday 7th for a engine light check picked my Chevy Avalanche up on Saturday and was unable to drive it do to them messing up my transmission they drove my truck for 26 mile now the truck will only drive in 2nd gear