Revocation of cancellation of registration allows application and requires a hearing before rejection; CGST revocations apply here. A registered person whose registration was cancelled by the proper officer may, subject to prescribed conditions, apply in the prescribed manner within thirty days from service of the cancellation order for revocation of cancellation. The proper officer may, in the prescribed manner and period, either revoke the cancellation or reject the application, but rejection cannot occur unless the applicant is given an opportunity of being heard. A revocation under the Central Goods and Services Tax law is deemed a revocation under this Act.