MySql command callback raised an exception (InvalidCastException: Specified cast is not valid.)
  at Oxide.Plugins.EnhancedBanSystem+c__AnonStorey18.<>m__0 (System.Collections.Generic.List`1[T] list) [0x000dc] in :0 

  at Oxide.Core.MySql.Libraries.MySql+MySqlQuery+<>c__DisplayClass24_0.b__0 () [0x0005d] in :0 

Another mistake is to write the command banlist mysql

Got the same problem! Did you found a solution?

banning works, unbanning give the error.