Transaction between related parties

I would like to have a clarification reg 3 small issues sir.


1. When there is a B2B transaction between related parties in which supplier charged half  price, the recipient is eligible for full ITC. now can we apply 2nd proviso to rule 28 of CGST rules sir?


2. In first question, I mentioned supplier has supplied at 50% of his cost to his related party. Can department ask supplier to reverse ITC to the extent of 50% because it was a gift to related party?


3. Whether proper officer under gst has any power to interfere with transaction value and ask why did u supplied at 50% less.


I would be privileged if I get a response from you sir. Tq