To avoid trouble both from the Customs Service, and from the auditors and law enforcement agencies to be certain of the authenticity and actual status of a certificate or declaration of conformity, you should know how and where to find the Register of issued certificates and declarations of conformity.
All issued and registered duly Certificates of Conformity, Declaration of Conformity, etc. on a mandatory basis is entered into the corresponding registers. Official register of certificates is available at the website of Rosackreditatsiya.
You're able without any problems to find the certificate or declaration of conformity to these links - you need to enter into this Register and by search engine to find a document issued with one of the details (number, name, etc.). If you can not find the certificate given to you in the Register long after its execution, you can demand explanations from the Certification Body issuing the certificate.