why can't I lose weight?

My name is Michael, 76, 200
Until about 6 years ago I weighed between 178 and 185. I have always been very active, working way past retirement age. A few months ago I woke up to find the scale telling me to get the guy behind me off the scale - 200+ pounds. NO WAY !! I immediately cut out most added sugar and salt. Nada.
I joined a gym, committed to a trainer for one year who in turn turned me on to MFP. That was two months ago. Once a week with the trainer, twice more without.
MFP tells me that based on info input I should weigh between 167 and some other number I forgot. Totally unrealistic as far as I am concerned. In my best year I didn't weigh that little. My goal is 185
Now comes the part that really bugs me. MFP tells me in order to lose one pound a week I must not exceed 1860 calories, Fine.
Adjustments are made. I can do this. I am too vain to look like the majority of old pregnant with twins looking geisers I know and schlepp belly fat around. And that is precisely where my 'problem' is. Across the ole belly and pubic bone. Nowhere else. My trainer tells me that my musculature is nothing short of amazing for a man my age. I can do things he has trouble having a 30-old do.
I have managed to stay well below the suggested count of 1860, hovering around 1650 for nearly two month. Just got off the #@!% scale: 199,6.
What's up with that??
I don't discourage easily and don't intend to give up.
I'd sure like to hear from a male my age, similar situation, who has who has conquered the beast of disgusting belly fat.