Rewards for watching Arcane Season 2's premier on your linked twitch.tv account can take up to 48 hours to reach your inventory. If it's already been two days and you still aren't seeing your rewards, submit a ticket with In-Game Question/Issue & In-Game Content Refund > Promotional Content > I didn't get my Arcane 2 premier Twitch drop selected in the dropdown list, and we'll help as soon as we can!