There are a few reasons that a waiver might not have been processed:
- The player you wanted was picked up by a member of your league who was higher in the waiver order than you.
- Overwatch specific: Your league is in-between weeks (Overwatch is a bi-weekly match up) and the player you wanted to drop has already played and is ineligible to be dropped for a new player.
- You did not successfully make a waiver priority list or it was made and then cancelled.
- Waivers take some time to process and it doesn't necessarily process exactly at 12 PM EST.
- If none of these issues apply and you believe there to be an issue, please reach out via support channels.