Furlenco - Credit not processed and cibil reporting threats

We ordered on furlenco last year in June **** for a period of * months, products were brought in a day however we struggled with furlenco who didn’t fix up the wardrobe. They delayed the installation for * months and finally set it up in **** September after much of follow-up , complaints and pleads. We then agreed with them when they decided to give us a credit for the same for * months. We waited and since it was time for renewal in December **** we paid up and there was no credit. Now we have been following up for the credit since it’s due renewal for another * months. However they neither respond appropriately and timely. Promise credits and then vanish. Keep sending me voice recorded messages, don’t answer calls and now have resorted to treating to report me on cibil.