Postgres Database : naming resctriction

hello everyone, i am using a cloud postgres database.

I deploy a soft i cant modify a lot, which try to connect to the database with **postgres** name.

If i understand well, this name seems to be kind of reserved because i cant create a database named **postgres**
Is there a solution in order to create a database named **postgres** or to connect and create user that can access it ?

Thanks a lot for your time