I suggest you wait a bit, due to the intensity of players trying to redeem the cape we came to this, mainly on the website, you can be sure that in a moment your account will be completely normal and your cape will arrive, but you can try downloading the installer from the website and tell us.
hello,
to start we recommend updating to the most recent version of Windows as follows:
Go to Settings > Update & Security > Windows Update > Press the “Check for Updates” button (even if it says everything is up to date).
The next step is to try resetting the Xbox app, Microsoft Store, and Minecraft launcher as explained below:
1. Press Windows key + I on your keyboard to open Windows Settings and click "Applications."
2. Find the app named "Xbox", select it, then click "Advanced Options", and finally click "Reset". Confirm the process. Repeat the same steps for the apps named "Microsoft Store" and "Minecraft Launcher."
3. Restart your PC and check if the issue is resolved.
I also add, if your problem is, try reinstalling the launcher from the official minecraft.net page
I hope I have helped you, otherwise we will follow up on your problem.