No idea what you mean by "produced when they should" as there is no set/fixed production time with any variety. Production onset is determined by the growing conditions.

But there are many possible explanations for any variety failing to continue production after the first flush of fruit. Again - all are growing conditions.

So we'd need all the details on the conditions you provided - name of variety, containers or ground, size of containers if used, feeding schedule, nutrients used, age of plants, pest or disease issues, water regimen, sun exposure, weather, your location, date planted out, etc.

Dave

PS: I assume by "growing from seed" you mean growing transplants and then planting them out at the proper time? If instead you mean direct seeding in their grow location then that raises a whole other set of possible issues.

im growing heirloom tomatos from seed and usually they will continue to bloom and set fruit into July.

I'm sorry but that doesn't answer any of the needed info questions I posted above. I suppose you could start by researching the condition called "Blossom Drop".

Dave

Depends on the temperatures. If the temps are higher than normal and above 90F, they may not set fruit. Don't know where you are, but that might be an issue.

Was it a determinate variety? If so they will produce all at the same time and that will be it. Please tell us the varieties you have!