Weird experience with Analytics with Sitecore 9.0.1 on Azure PaaS

Question

We are having a weird experience with Analytics with Sitecore 9.0.1 on Azure PaaS. Looks like the data is being processed on a single date hence we are seeing more than 20K visits on Nov-21. Whereas all previous days shows 300-320 Visits per day, which is obviously not correct. We had a deployment that day which probably broke the functionality. We verified that Fact_ChannelMetrics table doesn't have data after Nov-22. Whereas Interactions and InteractionLiveProcessingPool table have latest entries. We are seeing following exceptions in log files frequently.

2020-01-24T20:22:13  PID[4120] Error
5312 20:22:13 ERROR Cannot create tracker.Exception: System.InvalidOperationExceptionMessage: session is not initialized
Source: Sitecore.Analyticsat Sitecore.Analytics.Data.HttpSessionContextManager.GetSession()at
Sitecore.Analytics.Pipelines.EnsureSessionContext.EnsureContext.Process(InitializeTrackerArgs args)at (Object , Object[] )at
Sitecore.Pipelines.CorePipeline.Run(PipelineArgs args)at Sitecore.Pipelines.DefaultCorePipelineManager.Run(String pipelineName, PipelineArgs args, String pipelineDomain)at
Sitecore.Analytics.Pipelines.EnsureSessionContext.EnsureSessionContextPipeline.<>c__DisplayClass4_0.<Run>b__0()at
Sitecore.Analytics.XConnect.Diagnostics.PerformanceCounters.OperationPerformanceMonitorExtensions.<>c__DisplayClass1_0.<Monitor>b__0()at
Sitecore.Analytics.XConnect.Diagnostics.PerformanceCounters.OperationPerformanceMonitorExtensions.Monitor[T](OperationPerformanceMonitorBase monitor, Func`1 operation)at
 Sitecore.Analytics.DefaultTracker.EnsureSessionContext()at Sitecore.Analytics.Pipelines.CreateTracker.GetTracker.Process(CreateTrackerArgs args)at (Object , Object[] )at
 Sitecore.Pipelines.CorePipeline.Run(PipelineArgs args)at Sitecore.Pipelines.DefaultCorePipelineManager.Run(String pipelineName, PipelineArgs args, String pipelineDomain)at
 Sitecore.Analytics.Tracker.Initialize()

Verified all the possible root causes mentioned on this awesome blog post by Pete.

Is it something related to corrupted segments and reporting database rebuild is required? Additionally Personalization rules are not firing on production, is it related? My understandind is if CDs are collecting traffic there should not be any impact on Personalization.

Any inputs are greatly appreciated.