Seller refusing to Give proper B2B GST invoice

Yes you can claim such itc

Yes you're right

You are right, n u can take benifit of ITC credit

I only pay IGST.
And I believe that CGST & SGST are not applicable for inter-state transactions.
As such, my cleartax software is not even allowing me to make a purchase bill against such a purchase invoice, nor allowing IGST ITC.
Please advise.

Its an ineligible credit. you can not avail as ITC in the head off CGST & SGST.

Here the question will be Place of supply and consumption.
There may be possible that Goods are services has been consumed in the state of Seller then he has to report the taxes under CGST and SGST. Then ITC is not eligible.
if consumption is in your state, request vendor to rectify and you are eligible to avail ITC.

Yes you are right. If he is supplying from any other state then IGST will be implied. If he is supplying from the same state as that of yours then CGST-SGST will be implied. Also you can take such ITC (Input tax credit)
Know more about IGST ,SGST and CGST

Seller amended the invoice to charge IGST. So I suppose now I can get the ITC. Thanks friends.