Hi, I am Van. I'll be glad to assist you today.
The rewards list may vary from time to time. The Microsoft Rewards team may lessen the options of certain rewards or remove them from the list. One reason is that they run out of gift codes, or that the promotion for a certain reward has ended.
Unfortunately, Microsoft Rewards does not normally announce when certain rewards are being added or updated on the rewards list. We can only wait for them to release a new batch of gift codes.
For now, I suggest doing your daily activities to earn more points and checking your redemption page regularly for the latest reward updates.
In addition, you can also reach out to reward support by using the "Provide feedback" option on your account dashboard or using the link below. With this, the rewards team will be aware of your concern.
https://rewards.bing.com/support
Please let me know if you need any further assistance. I will be glad to help.