The way the event rewards work is:
When you collect enough 'tokens' to unlock a reward, you are then awarded the respective event reward and the required token amount is subtracted from your 'token total'. 

Example: 
- The first event reward costs 25 tokens to unlock
- The second event reward costs 55 tokens to unlock
In order to unlock both these event rewards, your total amount of tokens collected needs to equal 80 or more.