Greater Noida Authority — sewer choked

The sewer in front of our factory located at plot no 157 udyog kendra extension 1 ecotech 3 leading to seepage in our basement. Kindly attend as soon as possible. Kindly let me know whom to contact to hasten the job. A all other sewers in the factory have been cleaned by our plumber but the main manhole of the authority swere is choked leading to this problem