Subscriptions not working suddenly

Hi harshipsns,

I think this issue may related to your tenant setting, please contact to your tenant admin to check on it.(e.g. block settings, UPN settings...)

BTW, you can also take a look at below link to know the limitations of subscription feature.

Subscribe to a Power BI report or dashboard

Considerations and troubleshooting

• At the current time, subscribe is not available for dashboards or reports that come from content packs or Power BI apps. But there is a workaround...make a copy of the report/dashboard and add subscriptions to that version instead.
• Report page subscriptions are tied to the name of the report page. If you subscribe to a report page, and rename it, you will have to re-create your subscription
• For email subscriptions on live connection datasets, you will only get emails when the data changes. So, if a refresh occurs but no data changes, Power BI will not send you an email.
• Email subscriptions do not support most custom visuals. The one exception is those custom visuals that have been certified.
• Email subscriptions are sent with the report's default filter and slicer states. Any changes to the defaults that you make before subscribing will not show up in the email.
• E-mail subscriptions are not yet supported on reports pages created by the Power BI Desktop live connect to service feature.
• For dashboards subscriptions specifically, certain types of tiles are not yet supported. These include: streaming tiles, video tiles, custom web content tiles.
• If you share a dashboard with a colleague outside of your tenant, they will not be able to subscribe to the dashboard or its associated report pages. So if you are [email protected], you can share with [email protected]. But [email protected] cannot subscribe to the shared content.
• Subscriptions may fail on dashboards or reports with extremely large images due to email size limits.
• Power BI automatically pauses refresh on datasets associated with dashboards and reports that have not been visited in more than 2 months. However, if you add a subscription to a dashboard or report, it will not be paused even if it goes unvisited.
• If you are not receiving the subscription emails, ensure that your User Principal Name (UPN) is able to receive emails. The Power BI team is working on relaxing this requirement, so stay tuned.
• Sent reports and dashboards use your Power BI language setting. The default language is English. To see or set your language preference, select the cog icon  > Settings > General > Language.

Regards,

Xiaoxin Sheng