Autofill commands with own defined class

I have the problem with autofilling commands. Now I am writing an own .cls-File with all packages that I need.

When I use e.g. the code gls{}, it will be marked red and the autofill function is disabled.
When I write usepackage{glossaries} in the main part of my file and not in die .cls-File, then it works normally.

How can I fix it?