When was your endorsement application approved? As this is the point when you can start counting from in terms of the certificate package being shipped.
What did it say in the email advising you that your endorsement application had been approved about how long it would take the welcome kit (a.k.a certificate package) to arrive? It usually says it will take 8-12 weeks from this point.
Also, check the FAQ - again it is mentioning "up to 12 weeks" as being the time frame from the point when your endorsement application has been approved to the certificate package arriving:
https://www.isc2.org/Frequently-Asked-Questions#accordion-c6c19fcde9cf46cdadb06d7d6ed9719d
In summary, it can take up to 5 months from passing the exam to receiving the physical certificate.