Guys anyone to help me with that condition on my tomato

Hi Heindrives Evarest ! There are a number of fungal diseases that result in a stem turning black on tomatoes. Amongst these are Alternaria stem canker, phytophthora stem canker or .bacterial stem canker. If temperatures is not low with high humidity and spread of disease is fast form older plants,than it is bacterial canker. If temperatures is low at night than it will be definitely late blight canker in which leaves turn yellow and start dieing from the margins. If there are concentric rings on leaf spots than it will be early blight or Alterneria canker. At this stage for your I suggest spraying of tabuconazole followed by copperoxychloride fungicide or you can use Nativo fungicide of Bayer. For your information if you suspect bacterial canker which can be checked by oozing test than use copperoxychloride + tetracycline and try to reduce the moisture/ humidity. All the best.

Thanks Tufail Abbas bhai for your upvote and support

Thanks Glory Dickson for your upvote and support

Heindrives Evarest great effort for your upvote. But it came very late! Is every thing fine?