VCenter Access Issue Resolution

I'm unable to access Vcenter 6.7 running on VCSA due to an expired STS certificate. I've already restarted services and renewed certificates via the Vcenter console without success.

Key Requirements:
- Diagnose and resolve STS certificate issues
- Ensure Vcenter access is restored

Ideal Skills and Experience:
- Expertise in Vcenter and VCSA
- Strong knowledge of certificate management and troubleshooting
- Experience with Vcenter 6.7

Please provide a detailed approach and timeline.