im using this with EnhancedBanSystem and this happened lately

MySql command callback raised an exception (ArgumentException: An item with the same key has already been added. Key: 76561199163355508)
at System.Collections.Generic.Dictionary2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) [0x000c1] in <eae584ce26bc40229c1b1aa476bfa589>:0
at System.Collections.Generic.Dictionary2[TKey,TValue].Add (TKey key, TValue value) [0x00000] in <eae584ce26bc40229c1b1aa476bfa589>:0
at Oxide.Plugins.PlayerDatabase.<LoadMySQL>m4 (System.Collections.Generic.List`1[T] list) [0x00048] in <c4af9b7e0d924e50acb88a5dbe77a7b7>:0
at Oxide.Core.MySql.Libraries.MySql+MySqlQuery+<>cDisplayClass24_0.<Handle>b__0 () [0x0005d] in <7a75fa05cbc04391919cf072f240bf30>:0

i found out that i have to remove that specific steam id that is mentioned at the beginning of the error code from the mysql database, then it worked, i have no idea how did it get there twice... but after that it worked fine until some people reported that they got banned for ban evade, i searched the playerdatabase for a secondary account with the same ip (thats how ban evade works) and found none, later another person asked me again why he got banned for ban evade and again no second player with the same ip in the database, how is this possible? Is it giving out bans for ban evade just for fun?