Stored procedure error PLS-00201: identifier 'UTL_HTTP' must be declared
As you already figured out yourself, this seems to be a permission problem. Your user does somehow not have access to the UTL_HTTP package. Make sure your user has the EXECUTE permission on the package:
GRANT EXECUTE ON SYS.UTL_HTTP TO my_user;Note that you might have to do this as SYS.
Using SQL Developer (which I can recommend if you're doing PL/SQL development), see if you can then look at the package somehow. If that does not help, please post the permissions that your user currently has.