Mobile Iron build crash while rendering UITextview control

Question

We have an strange issue on Mobile Iron iOS devices, the application crashes each time while loading screen containing UITextview control, Other screen works fine.

The application works perfectly fine when installed on non mobile iron device.

Thanks in advance for providing any help in further debugging this issue.

More information:

Below is the crash log snippet:

13/08/2018 07:14:26 AM - MOB_APPLICATION - Error   Description: Error in AddControl with WizardAttributeId = 688 due to = , Message :The ObjectiveC class 'ACTextViewDelegateProxy' could not be registered, it does not seem to derive from any known ObjectiveC class (including NSObject)., StackTrace :  at MOB_APPLICATION.iOS.CustomControls.TextViewControl.configureTextView (System.String controlLabel) <0x104b04b50 + 0x00dd0> in <43ca0360be2c4376b18eba301a6ce7cc#2d993c574819398378e4eeb47a646433>:0 
  at MOB_APPLICATION.iOS.CustomControls.TextViewControl..ctor (MOB_APPLICATION.Shared.Model.WizardAttribute model, System.Int64 assetID, UIKit.UIViewController controller, System.String controlLabel) <0x104b04800 + 0x001f3> in <43ca0360be2c4376b18eba301a6ce7cc#2d993c574819398378e4eeb47a646433>:0 
  at MOB_APPLICATION.iOS.CustomControls.Control.AddControl (MOB_APPLICATION.Shared.Model.WizardAttribute attributeModel, System.Int32& controlHeight, UIKit.UIViewController controller, System.Int64 assetID, System.Boolean isAttrHistoryTime, System.Boolean isGrid, System.String controlLabel) <0x104ad45d0 + 0x014f7> in <43ca0360be2c4376b18eba301a6ce7cc#2d993c574819398378e4eeb47a646433>:0    DeviceInfo: iPhone | 11.4.1 | XXXXXXXXXXXXXXXXXXXXXXXXXXXXX | 1.0.74.2v

13/08/2018 07:14:26 AM - MOB_APPLICATION - Error   Description: Error in configureTextView with WizardAttributeId = 688 due to = , Message :The ObjectiveC class 'ACTextViewDelegateProxy' could not be registered, it does not seem to derive from any known ObjectiveC class (including NSObject)., StackTrace :  at Registrar.DynamicRegistrar.Lookup (System.IntPtr class, System.Boolean throw_on_error) <0x105002880 + 0x001e8> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at ObjCRuntime.Class.Lookup (System.IntPtr klass, System.Boolean throw_on_error) <0x105022b30 + 0x00033> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at ObjCRuntime.Class.Lookup (System.IntPtr klass) <0x105022b00 + 0x00017> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at ObjCRuntime.Runtime.ConstructNSObject (System.IntPtr ptr, System.IntPtr klass, ObjCRuntime.Runtime+MissingCtorResolution missingCtorResolution) <0x104ffb3e0 + 0x0001f> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at ObjCRuntime.Runtime.GetNSObject (System.IntPtr ptr, ObjCRuntime.Runtime+MissingCtorResolution missingCtorResolution, System.Boolean evenInFinalizerQueue) <0x104ffbc30 + 0x00077> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at ObjCRuntime.Runtime.GetNSObject (System.IntPtr ptr) <0x104ffbc00 + 0x0001b> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at UIKit.UITextView.get_WeakDelegate () <0x104fec7f0 + 0x0006b> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at UIKit.UITextView.get_Delegate () <0x104fea980 + 0x0001f> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at UIKit.UITextView.EnsureUITextViewDelegate () <0x104feccf0 + 0x0001b> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at UIKit.UITextView.get_ShouldBeginEditing () <0x104fecf50 + 0x00013> in <b7935acd70e343049845d6fd73e5ec44#2d993c574819398378e4eeb47a646433>:0 
  at MOB_APPLICATION.iOS.CustomControls.TextViewControl.configureTextView (System.String controlLabel) <0x104b04b50 + 0x00793> in <43ca0360be2c4376b18eba301a6ce7cc#2d993c574819398378e4eeb47a646433>:0    DeviceInfo: iPhone | 11.4.1 | XXXXXXXXXXXXXXXXXXXXXXXXXXXXX | 1.0.74.2v

What is "Message :The ObjectiveC class 'ACTextViewDelegateProxy' could not be registered, it does not seem to derive from any known ObjectiveC class (including NSObject)" about in above stack trace .

The app. is build upon Xamarin.iOS platform.