Xbox 360 console can't add profile

Sorry to hear it. Please try shutting the 360 down and then unplug your modem/router for at least 60 seconds. When your internet is back up and running turn on the console and try again. If your console has a wireless connection then please try using
an Ethernet cable

FIX: Xbox error code 80151103

1. Check for service alerts
2. Confirm your Microsoft account credentials
3. Reset your password
4. Download your Xbox Live profile again

1. Check for service alerts
If you find any service alerts when you check Xbox Live service status, give it a few minutes or wait for a while before trying it again, and check if the service is up and running. Usually, the status will be displayed as
up and running in green color with a green tick next to Xbox Live Core Services.

• RELATED: How to fix Xbox One fuzzy screen issues

2. Confirm your Microsoft account credentials
Xbox error code 80151103 can come up if your Microsoft account’s security information is not correct. In order to resolve this, do the following:

• Sign in to your Microsoft account. In case you forgot your password or are unable to sign in using it, you can check with the Lost
  Account or Lost Password troubleshooting on how to change it.
• Once you’re signed in, go to Security & Privacy
• Click Change password & more
• Under Security info helps keep your account secure, verify your email addresses and phone number
• You can add or update your security information as and when necessary
• Sign out and sign in again
• Try to sign in to Xbox Live

3. Reset your password
You can change your Microsoft account password by going to account.live.com and follow the prompts. Once you change it, sign in again
and try Xbox Live again.

Password changes are ideal if you think someone else is using your account, or the retailer you use h ad a security breach and you used the same password on your account, or you just want to change it for safety reasons.

However, if you forgot the password and know your email address, reset the password online by verifying your identity using other information. If you don’t know either information, use Lost account or Lost password solution
to reset it.

Note: You cannot change your Microsoft account password on your Xbox One console.

• RELATED: FIX: You cannot play online Xbox Live multiplayer, your account is set up

4. Download your Xbox Live profile again
If you still get Xbox error code 80151103 after trying the solutions above, redownload your profile again by doing the following:

• Move your Xbox Live profile by using a USB flash drive, plugging it into your console then go to the dashboard>settings>storage>all devices>gamer profiles (select your gamer profile). Select Move, then select the memory unit you want to move your profile
  to. Remove the USB flash from your console
• Clear the system cache by pressing Guide button, then go to Settings>System Settings>Storage/Memory. Highlight any storage device, then go back to your controller and press Y. Select Clear System Cache, and select Yes to confirm
• Restart your Xbox console
• Redownload your Xbox Live profile

You can't merge the 2 accounts together. In order to use the account you created online, you would need to download that account to the console -

support.xbox.com/.../add-remove-profile-xbox-360

hello RafaelC_550 y

I don't know which console you are on. to add a profile to an Xbox 360 go
here for Xbox 360.

to add a profile to an Xbox One go here for Xbox One.

You have to download the gamertag to the console. You can find instructions here -

support.xbox.com/.../profile-move-delete

Keep in mind it will be a separate account. You can't add it to a profile that is already on the console.