We are getting the error once we submit the sitecore 9.1 form. This is happening when we enable the the check box "Is tracking Enable" in sitecore core form. and this error is not with Standalone role, only with CD and CM server. The error is

[ArgumentException: alias should not be null or an empty string.
Parameter name: alias]
   Sitecore.Framework.Conditions.RequiresValidator`1.ThrowExceptionCore(String condition, String additionalMessage, ConstraintViolationType type) +100
   Sitecore.Framework.Conditions.Throw.ValueShouldNotBeNullOrAnEmptyString(ConditionValidator`1 validator, String conditionDescription) +121
   Sitecore.Framework.Conditions.ValidatorExtensions.IsNotNullOrEmpty(ConditionValidator`1 validator) +41
   Sitecore.Marketing.Core.Extensions.ConditionValidatorExtensions.IsValidAlias(ConditionValidator`1 validator) +139
   Sitecore.Marketing.Definitions.DefinitionManagerBase`2.GetByAlias(String alias, CultureInfo cultureInfo, Boolean includeInactiveVersion) +87
   Sitecore.Analytics.Data.DefinitionCollection`1.get_Item(String name) +156
   Sitecore.Analytics.Tracking.PageContext.Register(PageEventData pageData) +437
   Sitecore.ExperienceForms.Analytics.Tracking.FormEventsTracker.RegisterFormBegin(FormTrackingEventData pageEventData) +374
   Sitecore.ExperienceForms.Analytics.Tracking.FormEventsTracker.RegisterEvent(TEventData trackingEventData) +100
   Sitecore.ExperienceForms.Mvc.FormRenderingContext.RegisterFormEvent(FormEventData formEventData) +117
   Sitecore.ExperienceForms.Mvc.Controllers.FormBuilderController.Index(FormDataModel data) +271
   lambda_method(Closure , ControllerBase , Object[] ) +139
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +35
   System.Web.Mvc.Async.<>c.<BeginInvokeSynchronousActionMethod>b__9_0(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +39
   System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +70
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__11_0() +72
   System.Web.Mvc.Async.<>c__DisplayClass11_1.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +387
   System.Web.Mvc.Async.<>c__DisplayClass11_1.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +387
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.<>c__DisplayClass3_6.<BeginInvokeAction>b__3() +50
   System.Web.Mvc.Async.<>c__DisplayClass3_1.<BeginInvokeAction>b__5(IAsyncResult asyncResult) +188
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginExecuteCore>b__152_1(IAsyncResult asyncResult, ExecuteCoreState innerState) +26
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +68
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +52
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +39
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginProcessRequest>b__20_1(IAsyncResult asyncResult, ProcessRequestState innerState) +40
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +68
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +38
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +648
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +213
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +131