What does NaN on a return mean?

[Jasmin156174]

I recently returned two items online through the app and the Delivery status is "Nan". What does this mean? 

I tried looking online and on this website but all the support people just say "will private message you" on the conversations posted about this in the past. Is there an article or something on this? I just need my return. 

[iluvmadison]

If they don’t RECEIVE your return parcel with 30 days of ORDER, you’ll only get store credit—despite the slow transit times arriving to us to begin with. Really frustrating. 

[keelybt]

@Jasmin156174 This status typically means that it is still in transit back to us. The tracking should continue to update. Please note that it can take 3-4 weeks from the time you send it back to be received and processed.