MS Teams graph API stopped working

In our project we were using Microsoft graph teams chat and channel APIs. It was working earlier but it stopped working before a month. Now throwing exception related to subscription. On investigating I found that these are metered APIs and require subscription to be added. Now my doubt is how it was working earlier since last 1.5 years? Is the subscription and payment actually required?

Exception:

com.microsoft.graph.http.GraphServiceException: Error code: PaymentRequired

Error message: To call this API, the app must be associated with an Azure subscription, see https://aka.ms/teams-api-payment-requirements for details.

GET https://graph.microsoft.com/v1.0/users/0dt1863-601e-3269-bf4b-0sc9eh63b665/chats/microsoft

•graph.getAllMessages?model=B&%24top=200

SdkVersion : graph-java/v5.17.0

402 : Payment Required

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