Reputation is partly the memory of how consistently your words predicted your behavior.

A reputation is mostly a prediction. People are remembering how often your stated intentions turned into actions, and using that to guess what you will do next. Everything else, charm, credentials, the impression you make, is secondary to that record. It accumulates from ordinary commitments rather than from important ones.

Audit the last month of things you said you would do. Where the follow-through was missing, either do them or stop saying them. Saying less and doing all of it beats the reverse by a wide margin.