Hi @Sato
Yes, you need to use refresh token B to replace refresh token A, because the maximum lifetime of refresh token is 90 days, and this time cannot be modified, so when you keep using refresh token A, the token will expire after 90 days, so you need to use the newly obtained refresh token B to replace refresh token A. By analogy, you can continue to obtain refresh token C and new access token through refresh token B, then you need to replace refresh token B with refresh token C, so that you can always use new refresh tokens instead of old refresh tokens to prevent errors caused by refresh token expiration.
More information about refresh token:
https://learn.microsoft.com/en-us/entra/identity-platform/refresh-tokens
Hope this helps.
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