Hey there, REBATI RANJAN SRICHANDAN
If you are signing up to the Azure Student subscription, but have been unable to register due to your college not been recognised. This means that the system has not recognised your college/university as a verified education institution.
Please can you check if you meet the requirements for the subscription through this link here: https://learn.microsoft.com/en-us/azure/education-hub/azure-dev-tools-teaching/program-faq#azure-for-students
If you are eligible, please speak to your university/college about this and see if other students have been able to register and what they needed to do. If no one at your university/college has registered before, then please ask your university/collage if they have purchased a Microsoft educational licence for a product. If not, then they would need to do this using this article as guidance: https://learn.microsoft.com/en-us/microsoft-365/commerce/subscriptions/verify-academic-eligibility?view=o365-worldwide
Only after your university/college has done this, would your university/collage be registered as a verified educational institution. Then, providing you still meet the eligibility requirements for the Azure Student subscription, you should be able to apply for the subscription.
Hope this helps & happy holidays
Nathan