Unable to update watchOS

When I turn on my iPhone, I get the message “Your phone and Apple watch are unable to sync data for apps such as Mail and Acitivty. To continue syncing data with your iPhone, make sure your apple watch is on the latest version of watchOS.” I click “Update” on the iPhone and then click the watch icon for update. The message “Checking for Update” spins on the iPhone for several minutes, and then I receive the message “Unable to check for Update. An error occurred while checking for a software update.” Hitting “Try again” several times accomplishes nothing.

My watch (which does not require pairing with an iPhone) currently uses watchOS version 7.5. (The update is 7.6 something.) When I click on the Apple Watch for an update, I receive the message “Unable to check for Update. An error occurred while checking for a software update.”

I have turned the watch off, waited a while and turned it back on. I have tried to obtain the update with the watch connected to its charger and with a strong wi-fi connection,