"I didn't receive the new Esports League rewards/I lost Cup Points recently."
Esports League rewards can only be claimed following the monthly reset of Cup Points, at the beginning of the month (the first Monday of each month at 10:00 AM UTC).
Please note that the first monthly reset occurred on September 2, 2019 at 10:00 AM UTC. The Esports League players' Cup Points are reset according to their progression in the Esports Leagues the previous month. The more Cup Points you have, the more Cup Points you will lose. Also, players at the bottom of Esports League 4 are automatically demoted to League 1 following the monthly reset.
For more information on Esports Leagues, we invite you to check this blog post as well as this one.