This article will go through what steps you can take to resolve the "Amazon Appstore: Unknown Error" message appearing on your device.
After being in contact with Amazon Support regarding this issue, we believe it could be that the country settings on your Amazon account are not the same as your geographic location or where the device is being used. You have to update the location and payment method on your Amazon account.
We are not sure of the given answer but clicking on the OK button ScreenCloud would restart without you having to redownload the app from the store. If you want to speak to Amazon support, here is a link to get in direct contact with a member of their team: https://www.amazon.co.uk/gp/help/customer/contact-us
Unfortunately, we are unable to control this type of error from happening as Amazon devices are not manufactured through ScreenCloud. If this does not work best for you, we recommend a Chromebit or Chromebox as an alternative device. You can learn more about them by visiting https://screencloud.com/hardware.
If you have any additional questions on the Amazon Appstore: Unknown error, or any other questions or feedback about ScreenCloud, feel free to reach out to our support team at firstname.lastname@example.org or give us a call at our toll-free support line at +18885575335.