Belly button hard lump 6 months after mommy makeover. What can be done about this? (Photo)

Hi i had a MMO in Aprill 22. Alls been fine overall although i was slower healing. My button has a 1cm aprox hard lump. Its now gading in olur but still very much there. Imm unhappy with how it looks. I am told its over granulated and common. I was told to get foam dressing from my local nurse office but they refused and said it might be an undissolved stitch that would eventualy work its way out. However months later nothings changed other than the colour. My surgeon is not responding