sending/receiving friend requests on xbox one s

As stated above the gamer tags are case sensitive and need to be exact. Otherwise sadly it'll show as "not found". I'd double check and also make sure to link the xbox account to his epicgames account

Hi there,

if this is related to a specific game, then please mentioned the game (Fortnite?) or on Xbox Live itself too?

One thing that can be checked are the privacy and online safety settings here:
http://account.xbox.com/settings

to see if they will allow adding friends etc.

I assume your son's account is a child account and in such case the parental account needs to sign in at the link mentioned.

The parental account should be able to select the child account and alter settings like allowing to add friends and who can communicate with the child account etc.

If changes were made then keep in mind that the account need to sign out on the console and sign back in again.

Let us know the results

Another thing to consider is that are these 'Xbox' gamer tags? If you are trying to setup cross-play, you will need to set-up an Epic account and link your Xbox account to it. Then you can add other Epic account users their from other platforms.

Here is some quick guides:

https://www.epicgames.com/fortnite/en-US/news/fortnite-cross-platform-on-xbox-one

https://bestfortnitesettings.com/fortnite-cross-platform-crossplay/

Make sure that the Gamertags you are entering are xbox gamertags.

OR

Try changing the privacy settings:

https://support.xbox.com/en-US/my-account/security/manage-app-privacy-settings-xbox-one

One thing worth mentioning is that you need to make sure of is that the gamertag you are searching for is typed exactly correct into the search bar as Xbox won't show you similar gamertags. If you mistype it, nothing will show and the gamertag you tried
to search for may not exist.