Or you are not resting enough. To much cardio (and I love Zumba...so I really don't like to say that ).
I started gaining like crazy when I was trying to do Zumba, walk, and Beachbody Insanity. The harder I tried the more I gained.

Now...I'm lifting and walking with some Yoga and Pilates to try and get back to where I started.

And like Kristen said...probably not eating enough....

If you werent eating below your tdee whil you were pregnant or just after then the concept of doing TDEE for 2 weeks then 6weeks on the 15% cut from TDEE makes sense. I have read that. However, if you were eating below TDEE for longer periods, then doing the reset is 8-12 weeks at TDEE.

I don't know what your workouts or eating was like during pregnancy, but regardless now your still eating lower than TDEE and you do walk and move during the day beyond excercise to that is the right number for you.

Well, that's 1-3 hrs a week of exercise stacked on top of a otherwise sedentary desk job for 40 hrs and sitting commute.

You sitting for your equal 40 hrs during the day, or very active with baby?

Your base level is higher, exercise just stacks on top. 3 hrs cardio and 1.5 hr lifting weekly. (I'd suggest get more bang from your lifting by doing it first. You can't lift as heavy with tired muscles, which means you don't get as much beneficial changes from it)

There is 1 style to TDEE deficit method, exercise included in the TDEE level which you did, since included, you don't eat those calories back.

Or you can do MFP method, but do the more reasonable 15% deficit instead of block of calories off your non-exercise TDEE. In that case you do eat back exercise calories, with same 15% deficit to them too.

If you have that steady of a routine, do the TDEE deficit method.

Since you are still carrying known baby fat, I'd suggest getting a Katch BMR for the foundation of your math, as there is no way you have the avg LBM to fat mass ratio the other BMR's are assuming. Check out my profile page.
Those BMR's will be inflated for you, if it's 200-400 calories inflated, your deficit level of eating is not actually a deficit, but probably maintenance.

But you did right adding on the BF calories after taking off the deficit. Math method is right, I'd confirm the start of it though with that BMR.
And while it may be 3 x weekly, it's also 4.5 hrs weekly, which is moderate level if you want the rough 5 levels. Is 3 x weekly 30 min walk the same as 3 x weekly 3 hr walks? For that matter, is 1 hr walking the same as 1 hr running as 1 hr lifting?

But you were eating back exercise calories, so actually eating more than 2200, right?

There's a big difference between goal eating number and what you actually eat. Usually evidenced by review of food diary.

BMF will still be estimating, not actually measuring, what you are burning. But it or the FitBit are really good for the daily stuff.

Down to last 20 lbs, should be about 15% deficit too. The spreadsheet I referenced in my last post may suggest different depending on type/time of workouts.

Probably need to round up if using the rough levels, exercise was already at 4.5 hrs, almost top of the level. Probably round up to 2600 then take 15% deficit, then add 200 back on.

For BMR of 1593, and activity factor of 1.62 (based on 180 min high cardio, 90 min lifting, 40 hrs on feet moving weekly), I show TDEE of 2583.
Since you are doing lifting, and that means traditional heavy for you, sets and rests between them, not a bunch of bicep curls but good compound lifts working many muscles, you can take a good deficit for now, 18.6%.
So TDEG is 2102.
If you do an extra workout beyond what was included, log and eat it back. If it's included already, you don't.

Now, what changes all that is a better BMR estimate based on BF%. The above BMR is assumed 29% BF. If you are worse or better than best estimate BMR changes, TDEE changes, TDEG changes.