Thank you for submitting a question to Manage My Life. I know how frustrating it can be when appliances do not function properly.
Pull the dispenser out of the washer. On the right hand side of the dispenser, on the back of the front cover, there is a rectangular opening the size of the magnet. It has a plastic locking tab to hold the magnet in. Push the magnet in past the locking tab. I have included an image below that should demonstrate this.
If you do not feel confident repairing this problem yourself, then you can have it repaired at your home by a Sears technician. Here is a link for the website:
Sears Home Services
Here is a link that you may use to view the parts list diagram and for parts purchases;
Sears Parts Direct
I hope this is helpful. If I may be of further assistance as more details become available, please reply to this post.
Thanks again for using Manage My Life.