A user sends a messages using a specific sender ID. However, the recipient receives the message from a different sender ID.
The following reasons may have caused the issue:
•Sender Id on salesforce is not stored in 1xxxxxxxxxx format (where 1 is the country code)
•You may be sending SMS from a specific sender ID. However, the org has inserted a trigger on SMS History that updates the Sender ID. This is used for custom use cases, revolving around the round robin assignment of Sender ID.
Follow the given procedure to resolve the issue:
1.Ensure that that the sender Ids are always stored on Salesforce in plain format prefixed with the country code. This helps to make the sender ID routing logic on portal, work correctly.
2.Review the custom trigger and inform the customer accordingly. You can seek assistance from the CS team . If the issue, still persists, then, consult the dev team.