1.5 yrs Post tummy tuck, Foul odor coming from belly button area. What can be causing this and how can it be treated?

There are many potential reasons for your condition. To properly diagnose and treat this would require a physical examination. Schedule a visit with your surgeon who can better answer your questions and alleviate your concerns.

Is hard to know without pictures and examination, but could be that Your body has started to spit out one of the sutures used around this area. My recommendation would be to return to her surgeon. They likely will be able to tell whether this is the case. Otherwise continue to clean with soap and water