Bruh pg diploma in manufacturing management and B.tech are way too different you don't sound genuine student from any angle , sop is also just a optional document it helps a bit but doesn't leave a large impact , but what really matters is that you should be able to convince the VO that the course you have chosen is linked with your previous study and also you by looking at your profile if VO concludes that you can easily complete the selected course without any difficulties and good academic record. They will surely give you a visa no matter how many rejections you had previously.
JUST BE GENUINE!!!