Some themes (like Broadcast) have their own native subscription widgets pre-built into the theme.
Their native Broadcast subscription widget will display the subscription plans you created in Ongoing.
You can also disable their native widget and use the Ongoing Subscription widget.
From Shopify ➡ Sales Channels ➡ Online Store ➡ Themes ➡ Customize
From the Theme Builder ➡ click Product ➡ ☆Default Product ➡ click Form.
In the pop-up menu, unselect the "Enable subscription selectors" here & click Save
➡ Last step: Make sure you add the Ongoing subscription widget to your theme
You want the 👁 eyeball icon to be open, not shut.