I'm Nikhil and I live in Mumbai, India which is pretty hot and humid for most part of the year. I have been interested in gardening for quite some time and finally got a move on around 2 months back when I planted 4-5 odd plants. One among them was a pot of Black eyed Peas (also called Lobia in Hindi). They were growing at an amazing pace for around a month with really green leaves. Around 15 days back, there was a tinge of visible yellow on the leaves and they started withering. The leaves have now become sort of transparent and I can see the individual veins (at least that's what I think they are). I really don't know what the issue is! Could someone please help me out as this is my first shot at gardening

I have uploaded a picture for reference.
Thanks
Nikhil