I’m developing an Android kiosk app. I successfully paired the card reader, but it shows a “FailedToConnect (Please reinstall point of sale)” status. Even after resetting the reader multiple times and pairing it again, the connection still fails.
I’m wondering if it might be because I haven’t registered the app signing key fingerprint. I tried to register it, but I keep getting the message “Enter a valid SHA-256 certificate”, and I’m unable to proceed. I checked the SHA-256 fingerprint using ./gradlew signingReport.
Does the app also check the device location? I’m using application information of our customer account based in US, but the app is currently being developed in Korea.
What could be the issue?
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Based on the information you’ve provided, the following documentation will help answer your question:
Additional Documentation
Build on Android: Point of Sale API
Reader SDK Quickstart
Reader SDK Quickstart
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Just replying to say I’m also encountering the invalid SHA-256 error message when i try to add an app signature for android
i tried generating the certificate from the console as well as checking my certificate on the playstore dashboard and it just doesn’t seem to work no matter how i format it
What format is your SHA-256? Is it hexadecimal? 
the one I’m using is in this format
Okay it’s because you have : isn the SHA-256. You’ll need to create one that’s hexadecimal string without any colons. For example:
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
I removed the colons and typed in lowercase, and it got added.
Thanks!
Great, glad to hear that it’s working as expected.
