Call customer service to determine if you are in need of repair. Certianly sounds like it but they may have some steps to try.
If you have winter coming in your area, you may want to wait until the off season to bring it in. As you probably know, you can certainly use the mower without the SP engaged. Not ideal, but atleast you can still mow.
If you take it in for repair, contact Ego if it goes beyond 4 weeks as this is their acceptable time frame and they will get involved at that point if HD or other repair goes longer.
1-855-EGO-5656 (1-855-346-5656) from 8:30AM - 8:00PM EST (Monday - Friday) & 10:00AM - 6:00PM EST (Saturday & Sunday).