Yes, I am facing the same issue too. It is said that we have to apply by 28th in articles. However there is no link in the official website to apply. No idea on what to do.

Dear Aspirant

National Testing Agency (NTA), the conducting body of IGNOU OPENMAT MBA 2021 will conduct the same in online mode tentatively in April 2021. Complete details regarding the IGNOU OPENMAT MBA 2021 will be provided on the official website which is i.e. ignouexams.nta.nic.in in February 2021.

For more details use the link:

IGNOU OPENMAT MBA 2021 - Dates, Application, Eligibility, Answer Key, Result (careers360.com)

All the best