you dont eat enough.
And there is no argument you can make against that because your pictures tell the whole story
Your 63kilos and about 13%bf give or take that puts you around 5'10 max probably 5'9ish. Its obvious you train but your physique shows calorie restriction, your too lean for it to be a bad program, too little muscle (no offence) for it to be hormonal.
You say you eat lots but ill bet you dont, most guys your size post their diet and eat less than i do on a cut! Even if you DO eat a lot, eat more its simple, eat until you start to gain fat then adjust.
My prediction is that you eat a lot but not quite enough, then some days you dont eat anywhere near enough or go over 5 hours without food. Thus you dont get anywhere, truth sucks but theres no magic potion for guys of your body type, even steroids wont help without enough food!
also cant tell properly from pic but you could be quite young (under 21?) and possibly not caucasian, asian/arabic types struggle more than any to gain muscle but apologies if your just naturally tanned