Narrative:

While climbing out and talking to center; we were advised to participate with cpdlc (controller-pilot data link communications) clearances through center. We then acknowledge verbally and with cpdlc. We were given two route clearances in which we complied with via cpdlc with acknowledgments. Shortly after we received another clearance and it was to climb to FL330. We then acknowledge the cpdlc and commenced the climb to FL330. Shortly after reaching FL330; center asked us to confirm our altitude. We then told him we had complied with his clearance to climb and maintain FL330. He said he only showed FL300 as our clearance. We told him that our cpdlc clearance showed different. It show a clearance to climb to FL330. He then ask us to descend and maintain FL300; so we did. It was then that I took a picture of our ATC clearances on the FMC cpdlc page. The picture clearly shows a clearance to climb and maintain FL330. I have pictures on my phone of the ATC clearance; but there is no way to attach them to this form.

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Original NASA ASRS Text

Title: B767-300 flight crew reported a discrepancy between a data-link communication altitude and the altitude ATC required.

Narrative: While climbing out and talking to Center; we were advised to participate with CPDLC (Controller-Pilot Data Link Communications) clearances through Center. We then acknowledge verbally and with CPDLC. We were given two route clearances in which we complied with via CPDLC with acknowledgments. Shortly after we received another clearance and it was to climb to FL330. We then acknowledge the CPDLC and commenced the climb to FL330. Shortly after reaching FL330; Center asked us to confirm our altitude. We then told him we had complied with his clearance to climb and maintain FL330. He said he only showed FL300 as our clearance. We told him that our CPDLC clearance showed different. It show a clearance to climb to FL330. He then ask us to descend and maintain FL300; so we did. It was then that I took a picture of our ATC clearances on the FMC CPDLC page. The picture clearly shows a clearance to climb and maintain FL330. I have pictures on my phone of the ATC clearance; but there is no way to attach them to this form.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.