Is your rabbit on oral antibiotics, such as Baytril or Penicillin? Sometimes they need both. Abscesses should be completely removed, which may mean more than just lancing, then the rabbit would most likely be prescribed oral antibiotics for a week to 10 days (or longer). Jaw abscesses can be tricky and they sometimes occur due to tooth problems. Did your vet check out your rabbit’s teeth? That would need to be done under anesthesia. I don’t know what topical medicine you are putting on the abscess. There is a holistic treatment where Manuka honey is applied to the infected area, but I don’t know about other topical treatments.
It sounds like you need to make another trip to the vet to have him looked at. No rabbit likes going to the vet or having medicines forced on them, but the abscess needs to be dealt with and you also should find out how his teeth are.
I hope that he will be better soon and that the abscess will be totally taken care of.