Test the H5 page in the WeChat, but it report error at the second time when switch the context

I tested the H5 page in the Wechat with appium desktop.
First time, the code runs well. But when I ran it again, it showed error message “Chrome is not reachable”.
Then I changed to another real phone, it showed error message “Device XXX is not online”.

When I switch the context, it will show these message.

I test in Android phone: HTC M8ET, Android System Webview: 46.0.2490.76, Chrome explore: 46.0.2490.76, chromedriver: 2.18