Cannot "Assign Execution Authorization" due to missing privileges

Hi @all

So I want to assign execution authorization to an .hdbschema-File. I get the following error:

Authorization error: Missing EXECUTE privilege on "_SYS_REPO"."GRANT_SCHEMA_PRIVILEGE_ON_ACTIVATED_CONTENT"

So I logged in as SYSTEM and executed

GRANT EXECUTE ON "_SYS_REPO"."GRANT_SCHEMA_PRIVILEGE_ON_ACTIVATED_CONTENT" TO "I******";

with success.

Even though I cant assign execution authorization.

Any ideas?