What is your country? I guess you have to talk to support and let them know what your post office told you.
I’m in rural Spain. In the mountains above Malaga. The postal service is so lala here 
but my post office is reliable and I know them personally. If they say the card has not even been delivered to the local post office I believe them. This is why I think the transport company employed to send the card is simply lying when they say the card has been delivered
Hi, I haven’t received my card. I had to receive it on the 24 of June but nothing. How can I do ?
Read my posts here. 
Hello can i have assistance
Hi benbutler1971, this is a user community. There is no Revolut support. If you need specific help, you can reach Revolut via in-app chat, web chat, facebook, twitter or feedback@revolut.com