|If you are truly interested in attending these meetings in the future, you need to look at your attendance in the past. Can you honestly say that you made viable contributions to these meetings, or that your value to the company was enhanced by attending? The general manager may believe that your attendance is not the best use of your time. In this context, he is excluding you rather than forgetting you.
Assuming that your attendance at these meetings added value to the meetings or to you as an employee, you have already taken a good first step by discussing the matter with the general manager. Since this did not lead to an invite, you should discuss the matter with some of your associates who regularly attend these meetings. Ask them to let you know when the next meeting is scheduled. As soon as you learn the date, let the general manager know that you would like to attend. His response will let you know if anything lies behind his forgetfulness.