I'm new to the forum so if I misstep Let me know.
In 2019 I pulled 507 lbs of San Marzanos out of my garden!!!.
Since then the production has diminished.

I've tested the soil and found I was depleted on all levels so I added 15-15-15 from my farm store.
The pH was fine.
I did a liberal sprinkling in the beginning of April and a lighter one the beginning of May.
We start our plants indoors April 15th from quality seeds.
When we transplant them outside they're put in holes that are filled with a loam consistency.
We make a little semi circle around the plant (not touching the roots) and fertilize with 6-12-12.
We fertilize with 6-12-12 approximately 2 (ish) weeks later.
They have even consistent watering and are pruned well.
The plants aren't as tall as they have been but I do notice theres a lot of pruning. The nitrogen may be a little high.
We have healthy looking plants and there are lots of flowers but not much in the way of fruit.
I would love to relive my glory days having to pick too many tomatoes.
If I'm missing something or if I'm going at it all wrong any help is greatly appreciated.
I realize I've written a small novel here and I apologize. I just want to be specific in what I've done thus far.
Drew