Miles expiration question
For those of us with the US Miles and More credit card- one of the benefits is supposed to be not having your miles expire. I just had some expire and am trying to figure it out. Here it says you have to use the card every month…does anyone know if it’s just the three months prior to mileage expiration? Or if it’s every month since getting the card? https://www.miles-and-more.com/row/en/general-information/terms-and-conditions/no-mileage-expiration-credit-cards.html