As per the system restrictions, referral rewards are not credited to the users (Referrer) who share the same device with the Referee at any point (may be signed up on the same device or just logged in once on that device).
Though there could be many reasons due to which guests are not able to earn referral rewards. However, one of the major reason can be when the referrer and referee share the same device.
Please refer the image below to check the guests who share the devices:
In an effort to supply information as quickly as possible, this article has been published prior to a formal technical review, and is subject to factual, grammatical, and various structural errors. Data may be incomplete, misordered, or incorrect.
This additional disclaimer will be removed upon formal review of this article. The standard Punchh Inc. KB Disclaimer still applies, and can be found at: https://support.punchh.com/hc/en-us/articles/360040100273-Punchh-Inc-Knowledge-Base-Disclaimer