Error when setting Level up message

In a server people don't want pings on level up message.
I tried changing the default level up message to remove the

{user.mention}

{user.mention}

{user.mention}

{user.mention} (or to completely remove it.

Turns out you can't completely remove it. so i tried changing it to the variable

{user}

{user}

{user}

{user} which is then giving me this error.

Solution

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