I dunno how familiar are you guys with this, but this past week or 10 days I dealt with two cases of one customer returning after 90 exact days to claim he didn't receive the item, and another opening a stripe dispute claiming the same thing.
You might say, well I provide a tracking number and all is good, issue is, the USPS, royal mail and AU post etc, remove old tracking logs, so eventually you're left with nothing after 90-120 days.
For the first case, I tried using the wayback machine (I was desperate, but might work not sure tho) but turned out, the tracking number was still working on the royal mail tracking tool.
Fortunately, I got the right log still there to shut down this scam before starting.
My suggestion? keep track of deliveries with proof picture to avoid this kind of pattern, it's a bit of labor but better than having to give money to thieves.
Hope this helps.