When trying to redeem an offer on the Epic Games store, I came across this surprising error message:
Your account is unable to download any more free games at this time, please wait 24 hours before trying to redeem a free game again.
In my case, the message was triggered by my VPN. When I switched off my VPN, I was able to redeem the free game immediately (without waiting 24 hours). So it seems to be linked to IP as well as (or instead of?) user account, as the message suggests.