(8)Where the Issuing Authority or exporter or producer, as the case may be, does not furnish information within the specified time or the information furnished by him is not found satisfactory, the proper officer shall disallow the preferential tariff treatment for reasons to be recorded in writing:Provided that in case of receipt of incomplete or non-specific information, the proper officer may send another request to the Issuing Authority stating specifically the shortcoming in the information furnished by such authority, in such circumstances and in such manner as may be provided by rules.