3 years post op & have tip redness now & then - is it related to surgery? (Photos)

I had a septoplasty 3 years ago, it was done using my own cartilage from the nose and it was placed on the tip of the nose. And I have been seeing redness every now and then, but it doesn’t cause any pain nor breathing problem, it just gets red and it comes and go. Will it be related to the surgery? I have seen a surgeon here but I was told the nose was fine and was given antibiotics. It improved but it comes and go.