Problem with SQL in unity 2018.2

Hi everyone! i'am making a game using MySql. the thing is, i started it in unity 2017.3.1f1 but now i would like tu move it to 2018.2.8f1. My problem now is that in unity 2018.2.8f1 i can't connect my game to my database. i got this error :

 System.Security.Authentication.AuthenticationException: A call to SSPI failed, see inner exception. ---> Mono.Security.Interface.TlsException: Handshake failed - error code: UNITYTLS_INTERNAL_ERROR, verify result: UNITYTLS_X509VERIFY_FATAL_ERROR
   at Mono.Unity.Debug.CheckAndThrow (Mono.Unity.UnityTls+unitytls_errorstate errorState, Mono.Unity.UnityTls+unitytls_x509verify_result verifyResult, System.String context, Mono.Security.Interface.AlertDescription defaultAlert) [0x00036] in <93cc5a601cf645d2a15a96c4600351ac>:0 
   at Mono.Unity.UnityTlsContext.ProcessHandshake () [0x00075] in <93cc5a601cf645d2a15a96c4600351ac>:0 
   at Mono.Net.Security.MobileAuthenticatedStream.ProcessHandshake (Mono.Net.Security.AsyncOperationStatus status) [0x0003e] in <93cc5a601cf645d2a15a96c4600351ac>:0 
   at (wrapper remoting-invoke-with-check) Mono.Net.Security.MobileAuthenticatedStream.ProcessHandshake(Mono.Net.Security.AsyncOperationStatus)
   at Mono.Net.Security.AsyncHandshakeRequest.Run (Mono.Net.Security.AsyncOperationStatus status) [0x00006] in <93cc5a601cf645d2a15a96c4600351ac>:0 
   at Mono.Net.Security.AsyncProtocolRequest+<ProcessOperation>d__24.MoveNext () [0x000ff] in <93cc5a601cf645d2a15a96c4600351ac>:0 
 --- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <f2e6809acb14476a81f399aeb800f8f2>:0 
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0003e] in <f2e6809acb14476a81f399aeb800f8f2>:0 
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in <f2e6809acb14476a81f399aeb800f8f2>:0 
   at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in <f2e6809acb14476a81f399aeb800f8f2>:0 
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable+ConfiguredTaskAwaiter.GetResult () [0x00000] in <f2e6809acb14476a81f399aeb800f8f2>:0 
   at Mono.Net.Security.AsyncProtocolRequest+<StartOperation>d__23.MoveNext () [0x0008b] in <93cc5a601cf645d2a15a96c4600351ac>:0 
    --- End of inner exception stack trace ---
   at MySql.Data.Common.Ssl.StartSSL (System.IO.Stream& baseStream, System.Text.Encoding encoding, System.String connectionString) [0x00150] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.NativeDriver.Open () [0x0029f] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.Driver.Open () [0x0000e] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.Driver.Create (MySql.Data.MySqlClient.MySqlConnectionStringBuilder settings) [0x0004e] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.MySqlPool.CreateNewPooledConnection () [0x00006] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.MySqlPool.GetPooledConnection () [0x0008a] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.MySqlPool.TryToGetDriver () [0x0003f] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.MySqlPool.GetConnection () [0x0001c] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at MySql.Data.MySqlClient.MySqlConnection.Open () [0x0016d] in <74be5e8f18954f50971400e8a215dc5d>:0 
   at DB_Manager.Connect_BDD () [0x0001a] in C:\Users\Jo\Desktop\Turboplanet\Prototye1\TurboPlanet2018Version\Assets\Scripts\DB_Manager.cs:114 
 UnityEngine.Debug:Log(Object)
 DB_Manager:Connect_BDD() (at Assets/Scripts/DB_Manager.cs:118)
 DB_Manager:Start() (at Assets/Scripts/DB_Manager.cs:64)

i search a few things on google but i found no one with the same issues. So if anyone can help me find a way out it would be nice ! Thanks