you can cancel unused seasons and they will pro rate a refund. Send a ticket to customer service. The details for this are somewhere in the Terms of Use if you want to find them and quote them.
Here it is:
2. Dynasty Games. You may receive a refund for unused Dynasty Game (with the exception of Hardball Dynasty Game, which is governed by C.1 above) seasons if the request comes before the renewal deadline for the current Dynasty Game season you are participating in. If the unused seasons were purchased as part of a multi-pack, the maximum refund you may receive will be for the balance of the purchase amount minus the used seasons at the non-discounted price. For example, if you purchase a 10 pack of Hoops Dynasty seasons for $99.95 and use 5 of those seasons and request a refund for the remaining 5 seasons, you would receive a refund of $35.20 ($99.95 - (5 x $12.95)).