I have no credit on my account..

Sorry to hear it. When MS Points were transferred to Currency there was an expiry date for them. The currency had to have been spent by this past July otherwise they would expire and could no longer be used.

Currency added after the change have no expiry date so can be used when you choose to.

support.xbox.com/.../microsoft-points-retire-faq

The request deposit button is only available when you have at least 1,000 credits pending but less than 5,000. It's just so you can have them deposited before needing to have 5,000 pending first. Once you reach 5000, they are automatically scheduled to be
deposited by the following 15th or 30th of the month so there is no longer a need to request one.

Thank you, how much time can it take? I reach 6500 credits about one week ago

Hello,

From the FAQ on Vault Credits:

I claimed Rewards Credits from the vault. When will I receive them?

If you claim Rewards Credits from the MyVIP Vault, they should appear as pending in your account within 96 hours. Once they are pending in your account, the normal deposit process kicks in. Generally if you have over 5,000 Rewards Credits pending in your
account in the first half of any given month, that amount will be converted to your local currency and deposited into your Microsoft account on or around the 30th of that same month. If the Credits show as pending in the second half of the month, that amount
will be deposited into your Microsoft account on or around the 15th of the next month.

Please note you need at least 5,000 Rewards Credits pending to automatically trigger a deposit, though you can request a deposit for the next scheduled date as long as you have 1,000 Credits pending. Also, if you have ongoing issues with us depositing
into your account, such as your account not matching up with your billing location, you might want to consider choosing a different prize from the vault, as we won’t be able to deliver your Rewards Credits until the deposit issue is resolved.

They would be deposited at the end of the month then. On or before the 30th.

The request deposit button is only available when you have at least 1,000 credits pending but less than 5,000. It's just so you can have them deposited before needing to have 5,000 pending first. Once you reach 5000, they are automatically scheduled to be
deposited by the following 15th or 30th of the month so there is no longer a need to request one.