There are two checks you need to do before putting in your redirect_URI :-

1. There are restrictions when it comes to adding URIs in the app registration , check here

2. Please check if the redirect uri that ure adding is not duplicated in any sections , for example if the redirect_uri is 'http://localhost:3000' and the platform types added are single page applications as well as web redirect urls or mobile and desktop applications and any two of them have the same URI or something similar to 'http://localhost' as the port no. doesnt matter here , the client from which ure trying to access this app registration will always pick from the top and so you will get the error "AADSTS9002326: Cross-origin token redemption is permitted only for the 'Single-Page Application' client-type" (majorly when you are using SPA React or next apps) because it will think of it as a web redirect URI and not SPA