soften modern blinds

I had terrible experience, got my blockout blinds installed in April from Ari. Does not block light completely no matter how it is placed on roller, leaves 20 mm space between window frame and blinds from side view.Unhappy with work I requested to do something about it, in response I was told that replacing brackets will do the trick.Asked for fully payment on the visit which I did within 24 hours (still regretting) with assurance on fixing it in next visit along with remaining 2 blinds.You guessed it right, no response/visit after first installation to do follow up work(obviously received full monies, who cares). He has been completely ignoring my texts and phone calls for last 4 months, what a shame !NEVER AGAIN .!!