You have not specified what the rewards should actually give to the player. You have for example:
<RewardTier Name="ultra">
<Rewards>
<Reward Name="RTX 3090" Weight="100" />
</Rewards>
</RewardTier>
but it should be:
<RewardTier Name="ultra">
<Rewards>
<Reward Name="RTX 3090" Weight="100">
<Items>
<Item Id="1111" Name="RTX 3090" Amount="1" /> <!--- Replace 1111 with RTX 3090 item id -->
</Items>
</Reward>
</Rewards>
</RewardTier>
