Could not find stored procedure, however can execute it

Question

I am new to SQL Server and created my very first stored procedure. It executes fine and I can locate it under 'Programmability', 'Stored Procedures' so I pop open a new query and type in the following statements:

use name_of_database
exec name_of_stored_procedure 'value'

However before executing the stored procedure, the name of the stored procedure is underlined in red noting it cannot be found, so I run the query:

select * from INFORMATION_SCHEMA.ROUTINES where ROUTINE_NAME = 'name_of_stored_procedure'

Nada. It returns nothing.

However if I go ahead and execute the stored procedure, it works fine.

What am I doing wrong?