Reward Points Conversion

They would be scheduled to be deposited on the 29th.

Credits are deposited by the following 15th or 30th of the month after you have at least 5,000 credits pending. So if you get to 5,000 between the 1st and 15th, they are deposited at the end of the month. If you get to 5,000 between the 15th and 30th, they
are deposited by the 15th of the next month. 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 credits deposited before needing to have 5,000 pending first.

Sorry, I must have misread the post earlier. You'll need to post in the Xbox Rewards Questions support forum in order for Rewards support to look into it for you.

They would be scheduled to be deposited on the 29th.

Credits are deposited by the following 15th or 30th of the month after you have at least 5,000 credits pending. So if you get to 5,000 between the 1st and 15th, they are deposited at the end of the month. If you get to 5,000 between the 15th and 30th, they
are deposited by the 15th of the next month. 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 credits deposited before needing to have 5,000 pending first.

As I stated before I went over 5000 on march the 2nd, which means they should have been redeemed on the 15th. It's now april and still nothing.

I think you're referring to Rewards credits which are not the same as Microsoft points and are not even referred to as Microsoft points. The program's FAQ has the conversion rate for credits listed.

Support will check into it, but per the program's FAQ, 5,000 credits is equal to £3. So 50,000 should be £30.

It does sound as though you had some credits deposited, but your 50,000 may not have been part of that yet.