[Help] To restore original model number and bios

Recently I bricked my Dell inspiron 15 while performing bios update I took my machine to a repair guy to get bios flashed using programmer he was not able to find bios for exact model so he flashed bios of Dell vostro 15 which also shares same board now my machine model has changed and I’m facing headphone jack issue.
Can anyone guide me to get back original bios or is there anyway I can force flash inspiron 15 bios?