An automatically generated key is called a debug key / certificate.
You must create a new key that can simply copy it to both devices. The only drawback to this is that the build process is longer since you need manual steps.
Another option is to copy using a debug key from one of the systems.
You will find the keys in the .android folder .android in your home directory on Linux and in the user directory on Windows
Tip. Never lose a certificate as soon as you click on the application to the market.
Ravi vyas
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