Estimate could not load: 404 error found

[rishabh-1004]

Issue: Getting error while loading session in Estimate extension like "Estimate could not load: 404 error found " in Azure devops server 2020 on-Premise.

[AnnaZakomoldina]

+1 similarly 404
uncaught at Xn at Xn
at p
at $n
TFS.WebApi.Exception: 400: Bad Request
at Object.

[rianamonshouwer]

+1 same error 404 : Could not load session

[leguanjoe]

Same problem with Azure Devops Server (on-premises)

[hello2tomoki]

Same problem with Azure DevOps Server 2019 (on-premises)

[careywalker]

I am getting the same issue with Azure DevOps Server 2020.

It is trying to access this URL:

http://myinternalservername:8080/azure/DefaultCollection/_apis/ExtensionManagement/InstalledExtensions/ms-devlabs/estimate/Data/Scopes/Default/Current/Collections/EstimationSessions/Documents

And this is the error:

{"$id":"1","innerException":null,"message":"%error="1660002";%:The collection does not exist\r\n%error="1660002";%:The collection does not exist","typeName":"Microsoft.VisualStudio.Services.ExtensionManagement.WebApi.DocumentCollectionDoesNotExistException, Microsoft.VisualStudio.Services.ExtensionManagement.WebApi","typeKey":"DocumentCollectionDoesNotExistException","errorCode":0,"eventId":3000}

I'll clone the repo and see if I can figure out what's causing the issue.

Also, it's making this type of request as well that does succeed:

http://myinternalservername:8080/azure/DefaultCollection/_apis/ExtensionManagement/InstalledExtensions/ms-devlabs/estimate/Data/Scopes/Default/Current/Collections/sessions-96df8c55-5805-437f-86b5-e06b49f947d5/Documents

[Tatzoof]

Same issue here.
On Azure DevOps Server on-premise
Version Dev17.M153.3

What is strange is that it works with some collection while having this issue on other. Although I can't find any differences in their configuration.