Tata Oberai motors - Defective vehical

I have' financed A new tata vehical intra v** for commercial use on june * after **** km of run on ** july night vehical is getting problem of race it is not taking speed more than ** kmph and meter is showing check engine sign
After that mechanic told to bring it on workshop he opened the job card on ** july and told us that rytnow they dont have laptop to repair the problem then i complaint in tata toll free number after that they customer care executive talked to workship manager Mr. Deepak kandari after all they arranged laptop and try to sort out the problem anyhow signed gone from meter and speed come back in vehical but on ** july again the same problem we get and company guy told to bring it again on workshop
We are unavle to deliever our order on time due to this defective vehical so how can we pay the bank emi plz help