The Install URL (which can either be a link or a QR code) is what links a device to its designated location. It needs to be opened on your chosen Android device with the In-Store Merchant App already installed.
The reason why you see this error may be because of one of three ways:
1. The link may have already been used.
You may only have one linked device per location. That said, the link you tried to open on this device may have been designated for another location with a device already linked, or the location simply has another device linked. You can try to either generate a new Install URL or unlink the other device in order to use your chosen one.
2. The link may have already expired.
If unused for a month after adding the location to your Restaurant Alert + Deliver app within your Shopify store, it expires. This is for security reasons.
3. The device may already have a location linked to it.
You may only have one location per device. If you would like to log in to another location with this device, you would need to unlink the location first and generate a new Install URL.
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