Refresh issue in desktop

Power BI will typically reuse stored credentials when connecting to the same data source, so you shouldn’t need to re-enter your ID and password each time. However, this only works if the source is recognized as the exact same connection. If the data source belongs to a different account (for example, a similar dataflow hosted under another tenant or login), Power BI treats it as a separate source and won’t reuse the existing credentials.

In your case, the issue happens because each report may be tied to slightly different data source definitions or credential scopes. So even if they look identical, Power BI doesn’t always carry over the authentication.