Can I create a login system in Unity without using Photon authentication?

I'm having trouble making a login system inside Photon for Unity, I've already tried to do everything, I ran the entire Google and tried everything but I always have some mistake! On my last attempt I got this error on my Unity console:

 Operation failed: OperationResponse 230: ReturnCode: 32755 (Custom authentication service error: Error). Parameters: {} Server: NameServer
 UnityEngine.Debug:LogError(Object)
 NetworkingPeer:OnOperationResponse(OperationResponse) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs:1623)
 ExitGames.Client.Photon.PeerBase:DeserializeMessageAndCallback(Byte[])
 ExitGames.Client.Photon.EnetPeer:DispatchIncomingCommands()
 ExitGames.Client.Photon.PhotonPeer:DispatchIncomingCommands()
 PhotonHandler:Update() (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/PhotonHandler.cs:158)

And also this other error:

 Custom Authentication failed (either due to user-input or configuration or AuthParameter string format). Calling: OnCustomAuthenticationFailed()
 UnityEngine.Debug:LogError(Object)
 NetworkingPeer:OnOperationResponse(OperationResponse) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs:1660)
 ExitGames.Client.Photon.PeerBase:DeserializeMessageAndCallback(Byte[])
 ExitGames.Client.Photon.EnetPeer:DispatchIncomingCommands()
 ExitGames.Client.Photon.PhotonPeer:DispatchIncomingCommands()
 PhotonHandler:Update() (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/PhotonHandler.cs:158)
 

So I got tired of using Photon Auth, and wanted to know if I can create a login system inside Unity itself, not Photon, Photon will only show the names of the players to the other players, and other things normally. Is there a problem with authentication being only on Unity and not on Photon?