curatio

Hi,
you have to set the expansion of your choice in the database. See https://www.getmangos.eu/wiki/referenceinfo/dbinfo/realmdb/account-r1/#expansion
If you created a new account, the default expansion is 0. This means that this account has no expansions. For TBC you have to change it to 1.
 
or you could do this in game with an administrator account:
 account set addon   Syntax: .account set addon [#accountId|$accountName] #addon Set user (possible targeted) expansion addon level allowed. Addon values: 0 - normal, 1 - tbc, 2 - wotlk. Source: https://www.getmangos.eu/wiki/referenceinfo/dbinfo/mangosdb/mangoszeroworlddb/command-r1006/