My watch reads “clear all” with an X in the middle.

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clear all came up on my watch and i canno… - Apple Community

Hi Dsweetboy You will need to tap on the X this happens if we swipe down for the notifications. pressing the X will clear all notification.

If your screen is Frozen force restart the watch You should force restart your device as a last resort and only if it's not responding. To force restart your Apple Watch, press and hold both the side button and Digital Crown for at least 10 seconds, then release both buttons when you see the Apple logo.

Hope this helps.