Walgreens Healthcare Clinic

On Oct 18, 2017, I visited the Walgreens Clinic at 121 Northshore Dr. Knoxville TN. I waited 45 minutes to be seen and was immediately turned away for not having a physical copy of my health insurance card despite having the open app available on my phone for scan and presentation of all pertinent insurance information. I never asked for the visit to be billed to my insurance and offered payment in full to be seen, but was refused because the physical card was not available. How is this service? I have insurance and all information in the format provided by BlueCross Blueshield of TN. I have funds to pay for the visit in full. What's their problem?