Selenium::WebDriver::Error::UnknownError causes socket hang up, followed by ECONNREFUSED 127.0.0.1:8200

Question

I'm developing an automation script to exercise an app on a tablet. The script is written on a MacBook Pro with OS X v10.11.6 in RubyMine 2018.3.5 and connects via Wi-Fi to the tablet using Appium 1.12.1 and Gem selenium-webdriver 3.141.0.

The Capabilities declarations for Appium in RubyMine are

appiumVersion: '1.12.1', platformName: 'Android', platformVersion: '7.0', deviceType: 'tablet', deviceName: '10.124.41.103:5555', app: '/Users/paulkmecak/Downloads/usa-mailing-qa-signed-686.apk', appPackage: 'com.pb.csdsenior', appActivity: 'com.pb.csdsenior.presentation.view.activity.StartupActivity -esa REDIRECT_ACTIVITY com.pb.csdsenior.presentation.view.activity.MailMainActivity', newCommandTimeout: 480, noReset: true, fullReset: false, automationName: 'UiAutomator2'

The Hipstreet Titan Turbo tablet runs Android 7.0

The script reads records with various parameters and enters them on the tablet app, making sure the results on screen 1 carry over to screen 2, etc, and back to the home screen.

At some random point, I get an error message

***Error Type: Selenium::WebDriver::Error::UnknownError, Error Message: An unknown server-side error occurred while processing the command. Original error: Could not proxy. Proxy error: Could not proxy command to remote server. Original error: Error: socket hang up,

find_element_by_locator( COD ), Error Type: Selenium::WebDriver::Error::UnknownError, Error Message: An unknown server-side error occurred while processing the command. Original error: Could not proxy command to remote server. Original error: Error: connect ECONNREFUSED 127.0.0.1:8200 undefined method `click' for # (NoMethodError)***

This occurs after as few as 45 records or as many as 189 records. Unfortunately, there are over 1600 records I need to process.