Hi Shohamb,
It sounds like when you press the Action button, your workout is paused. Let's make sure you have the settings correct for the Action button. Use the below steps for guidance:
- "Open the Settings app on your Apple Watch. You can also do this in the Apple Watch app on your iPhone.
- Tap Action Button.

3. Tap the menu under Action, then select what you want the button to launch.

4. Tap the arrow in the top-left corner
to go back to Action Button settings.
5. Tap the menu under App if it appears, then select an app to perform the action. Some actions, such as Flashlight, don't show the App option.
6. Tap the arrow to go back.
7. Tap the menu under First Press if it appears, then select an action. Some features allow different actions to happen on the first and second press of the button."
This information is from Use the Action button on Apple Watch Ultra - Apple Support.
Take care.