Not getting a reward from Microsoft rewards

You would need to contact customer support for the Microsoft
Rewards program.

For help with the rewards program, you would need to post on the Xbox Rewards Questions support forum.

According to rewards support they should be restocking items. Microsoft does not run the Xbox Rewards program so the amount of credits they get is dependent on what they get from Microsoft.

From the Microsoft Rewards Migration FAQ: "any unredeemed MyVIP Gems will be converted to Microsoft Rewards points and can be used to redeem rewards from the Microsoft Rewards catalog once your membership is transitioned. One MyVIP Gem will
convert to one Microsoft Rewards point".

From the Microsoft Rewards Migration FAQ: "any unredeemed MyVIP Gems will be converted to Microsoft Rewards points and can be used to redeem rewards from the Microsoft Rewards catalog once your membership is transitioned.
One MyVIP Gem will convert to one Microsoft Rewards point".

You got it right, convertion rate will be 1:1.

From the Microsoft Rewards Migration FAQ: "any unredeemed MyVIP Gems will be converted to Microsoft Rewards points and can be used to redeem rewards from the Microsoft Rewards catalog once your membership is transitioned.
One MyVIP Gem will convert to one Microsoft Rewards point".

They have been restocking the Vault lately, but I agree the most requested prizes get out of stock pretty fast...