Cannot open Team Project resource in Azure portal after I have transfered subscription

I have transferred my Azure Subscription from personal Microsoft account to company account.

Now, when I log in to azure portal using company account, I see my team project resources (now called DevOps project). When I try to open it, it never loads:

I'm also unable to fix my Azure Resource Manader Service Endpoint in VSTS, where I still log in using personal account

EDIT: I see certificate error in browser's log:

SCRIPT7002: XMLHttpRequest: Network Error 0x800c0019, Security certificate required to access this resource is invalid.

When I acccept the certificate I get:

https://tfsprodweu2.cloudapp.net/signalr/negotiate?Authorization=Bearer%20e... No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'https://azuretfsextension.hosting.portal.azure.net' is therefore not allowed access. The response had HTTP status code 404.