USPS shows delivered to a parcel locker but customer can not find it

[boneplate]

The USPS tracking shows the package was delivered to a parcel locker in the apartment building but the customer states they cannot find the package in all of the lockers. They have started a refund claim. Am I responsible for refunding the customer and filing a lost claim with USPS? Does Ebay guarantee and cover the refund? Or am I out the money? Please give me tips. thank you

[rock.star]

You are not responsible. Enter the tracking number showing delivery into the case and it should be closed in your favor. 

The buyer needs to get with to Post office to try and find out what happened.