Error after installing a patch

[lukazec 0]

So basically I've just installed the 1.1.0b Patch to my Cities Skylines and the game starts normally until it has to load the menu,then it lags very hard.

Somehow I manage to start the game and when I open it it opens an error and when I copy it to clipboard this is the code I get:

Method not found: 'CitizenManager.GetGroupCitizenInfo'. [System.MissingMethodException]

Details:
No details
System.MissingMethodException: Method not found: 'CitizenManager.GetGroupCitizenInfo'.
  at CSL_Traffic.CustomFireTruckAI.ArriveAtTarget (UInt16 vehicleID, .Vehicle& data) [0x00000] in <filename unknown>:0 
  at CSL_Traffic.CustomFireTruckAI.SimulationStep (UInt16 vehicleID, .Vehicle& vehicleData, .Frame& frameData, UInt16 leaderID, .Vehicle& leaderData, Int32 lodPhysics) [0x00000] in <filename unknown>:0 
  at VehicleAI.SimulationStep (UInt16 vehicleID, .Vehicle& vehicleData, UInt16 leaderID, .Vehicle& leaderData, Int32 lodPhysics) [0x00000] in <filename unknown>:0 
  at CarAI.SimulationStep (UInt16 vehicleID, .Vehicle& data, Vector3 physicsLodRefPos) [0x00000] in <filename unknown>:0 
  at FireTruckAI.SimulationStep (UInt16 vehicleID, .Vehicle& data, Vector3 physicsLodRefPos) [0x00000] in <filename unknown>:0 
  at VehicleManager.SimulationStepImpl (Int32 subStep) [0x00000] in <filename unknown>:0 
  at SimulationManagerBase`2[Manager,Properties].SimulationStep (Int32 subStep) [0x00000] in <filename unknown>:0 
  at VehicleManager.ISimulationManager.SimulationStep (Int32 subStep) [0x00000] in <filename unknown>:0 
  at SimulationManager.SimulationStep () [0x00000] in <filename unknown>:0 
  at SimulationManager.SimulationThread () [0x00000] in <filename unknown>:0 

 

If you have any suggestions, please help...

Thanks.