FB abs completed- but still can't lose the last 5 lbs!!

I'm feeling bummed today. I have mixed emotions about completing my last day of FB Abs round 2 yesterday. I wish I felt accomplished, but I feel like it didn't get me to my goal. I want to start by saying that I have lost about 15 lbs over the past 3 years and I am proud of that- I am so much stronger, my shape is leaner, and I am able to do a lot of varied and intense workouts which makes me feel awesome.... but... I just can't lose that last layer of fat over my tummy. I used to have a flat tummy and I really want to get back to that spot to where I'm not afraid to wear form fitting shirts or bikinis without sucking in and constantly being aware of my midsection. Don't get me wrong, my abs are super strong and toned and they do show a bit, But I still have that little layer of belly fat and it's been over 6 months trying to lose it, and it just seems like it won't go away. I also have a really sensitive stomach (almost like IBS) and it has taken months of trial and error with my diet to keep my severe bloating under control, so I have always had a lot of insecurity around that area of my body.

I'm so frustrated because I'm really trying hard to accept myself the way I am - I am in great shape and I do feel like I look good, But somehow I just feel like I haven't reached my goal. Sometimes I think maybe this is just how my body is supposed to look, and I'm not meant to lose that belly fat, Did anyone else struggle with this and have any advice for me?? Is it an unrealistic goal to have a flat tummy? I don't want a six pack, but I just want this fat to go away. I don't know what I'm doing wrong. I'm eating clean, at a calorie deficit, and working out 4x week on average.

Any advice is appreciated!!

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