ERROR: failed to verify issuer credentials for 'identity.linkerd.cluster.local' with trust anchors: x509: certificate has expired or is not yet valid

The first error you point out has some contradictory data:

certificate has expired or is not yet valid: current time 2023-12-13T13:40:50Z is after 2023-12-13T13:40:08Z
Invalid After 2023-12-15 13:40:13 +0000 UTC

Can you post the full issuer certificate?