After in agreement with Sh.Ganeshan Kalyani Ji, I further add as follows :
ITC cannot be denied if you conform to the following conditions/parameters/basic requirements :-
1. Tax paid invoice in original .
2. Physically receipt of goods or services.
3. Used the said goods or services in the course of business or furtherance of business (taxable not exempted).
4. Full payment to the supplier within stipulated period.
5. Proper entry of the goods/services and payment made in the books of accounts.
6. Availment of ITC is not hit by time bar limit under Sections 16 and 18 of CGST Act
7. Inputs/capital goods/services are not hit by Section 17 (5) of CGST Act.
If you fulfill the above conditions, technical lapses committed unknowingly on common portal cannot be a hurdle in availing ITC. There are case laws of various courts on this issue in the assessee's favour. Everybody wants to avoid unnecessary litigation. Everybody wants to avoid interest and penalty. The compliance on common portal is also legal requirement which cannot be ignored. We cannot forget that the basis of compliance on common portal is the fulfillment of above seven conditions which are primary requirements..