Exception in thread "main" org.openqa.selenium.InvalidArgumentException: invalid argument: invalid locator (Session info: chrome=78.0.3904.108)

I ma getting this error:
Exception in thread “main” org.openqa.selenium.InvalidArgumentException: invalid argument: invalid locator
(Session info: chrome=78.0.3904.108)

I am using appium server, Android emulator and on the mobile app is hybrid so not able to locate the ids provided by developer.
Please help.