Hey - Googling "Sql Server Error 18456" leads me here - https://docs.microsoft.com/en-us/sql/relational-databases/errors-events/mssqlserver-18456-database-engine-error?view=sql-server-2017

Sounds like it is a Logon Failed error meaning your username or password is incorrect.

The error reason An attempt to login using SQL authentication failed. Server is configured for Windows authentication only. can be returned in the following situation:
When the server is configured for mixed mode authentication, and an ODBC connection uses the TCP protocol, and the connection does not explicitly specify that the connection should use a trusted connection. To resolve this issue, include TRUSTED_CONNECTION = TRUE in the connection string or you can: fix sql error