Hi Leedj. You'd be better off with fattier cuts of meat, added butter, mayonnaise, fatty dressings, heavy whipping cream, olive and coconut oil, etc. and to get rid of shakes. Yogurt is also borderline. Which version of Atkins are you doing?
I have been on an Atkins based diet for 7 months and did very well with 25 pounds gone in about three months. What I did is start at induction and gradually added tiers up to tier 5 (with limited quantities at higher tiers) and rarely stray from that level.
I highly recommend you read one of Dr. Atkins' books to truly understand the diet. You are not doing it right. It should be low carb, high fat, moderate protein. There are varying opinions on macro ratios, but generally fat is higher than protein and you have that reversed. 200 is probably at least 80 more than you need, but you do work out a lot, so can probably tolerate more than most of us.
Also, I ate real foods. The Atkins shakes and packaged foods aren't helpful. Even if you're using other shakes, some proteins can spike insulin (whey I think), so could be hindering your efforts. The Atkins website is designed to sell. That's it. Most on here call their products frankenfood.
Here is a link to the book I read and loved. It clearly explains the science and why low carb, high fat works. It's an easy read and under $6 for kindle download.
https://www.amazon.com/Dr-Atkins-Ne...diet+revolution
Here is a link that is also very helpful.
https://www.dietdoctor.com/how-to-lose-weight