Database Error Duplicate entry '246' for key 'PRIMARY' help

Hello rage.
I have been working on a r63b hotel using ubercms 2.0 (i think) with plusemu r2
The emulator will accept connections from my client, but the client wont connect fully, the emulator stops the connection and says critical error logged, so i took a look and found this

Code:

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Bug duing user login: System.FormatException: Input string was not in a correct format.
  at System.Number.ParseDouble(String value, NumberStyles options, NumberFormatInfo numfmt)
  at System.Double.Parse(String s, NumberStyles style, IFormatProvider provider)
  at Silverwave.HabboHotel.Users.Authenticator.HabboFactory.GenerateHabbo(DataRow dRow, DataRow mRow, List`1 group) in c:\Users\Administrator\Desktop\Invitee Fixed Revision 2\Silverwave Emulator\HabboHotel\Users\Authenticator\Authenticator.cs:line 37
  at Silverwave.HabboHotel.Users.UserDataManagement.UserDataFactory.GetUserData(String sessionTicket, String ip, Byte& errorCode) in c:\Users\Administrator\Desktop\Invitee Fixed Revision 2\Silverwave Emulator\HabboHotel\Users\UserData\UserDataFactory.cs:line 440
  at Silverwave.HabboHotel.GameClients.GameClient.tryLogin(String AuthTicket) in c:\Users\Administrator\Desktop\Invitee Fixed Revision 2\Silverwave Emulator\HabboHotel\GameClients\GameClient.cs:line 134

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But i did notice that when i tried to register on the cms, it came up wit this error after submiting the application Database Error Duplicate entry '246' for key 'PRIMARY'

How can i fix this whats happening ?
can someone post a fix