PLF? PLR?

I never heard of a PLR. A PLF is a Passenger Locator Form that must be filled out before arriving in Greece. Actually it should be filled out before leaving for Greece. Here's a link to the website with all the information for Greece. Most, if not all, European countries are now requiring something like this because of the COVID situation.

They want to be able to know where to reach you, if something happens - like the person two seats from you on the plane turned out to be positive for Covid-19, or some other exposure concern arises. Some reports are that people didn’t have the form completed early, and were still able to travel, but were delayed and had a hassle, when getting the PLF and being e-mailed the all-important QR code can be done now. Actually, what we got for upcoming Italy trip (in 2 days) is a dPLF - digital Passenger Locator Form. After submitting the dPLF application, we were each e-mailed a QR code image, containing our pertinent info, but also printed out the e-mail and QR image, so we had a paper backup copy. With just a week to go, get your dPLF application started ASAP.

We returned from Greece on 9/28 after first going to Croatia and no one in either country or any airline ever asked for or looked at our PLFs - no one. The vaccine card was constantly asked for, however.

Plf, just go online and you get it immediately. At least we did. They checked each time we arrived in Athens on September 5th and the 17th. We couldn't even check in online when coming back from from Istanbul to Athens until we showed the PLF and our covid info.