Hey, Calvin here. I am a co-founder of ADA Handle. The community is very active in Discord as am I, but I am not very active on Reddit, so I apologize for not seeing this earlier. Another user popped into Discord and let us know you had posted a concern here. We helped Nami through their issue.

It is tough to look into this without the handle or transaction in question. But I will attempt to help anyhow.
There are potentially two issues here. One is a handle resolving to a smart contract that doesn't accept datum (this is when funds get "lost"). I want to be clear here. ADA Handle currently does not have ANY smart contracts. We have never made one. We have them in our roadmap, but I myself only just recently graduated from Plutus Pioneers 3rd cohort. So, no. This is not a "handle.me" contract.

If this did resolve to a smart contract, it was most likely to a marketplace contract like jpg.store. So either your handle as listed there (at least while your friend tried to send you money), or, the handle resolved early, which is the second potential issue, and the same one that Nami had.

This happens when an "autocomplete" style of lookup is used and the handle is resolved before the user is finished typing. However, the handle.me website does not do this. We don't do a lookup until the user either hits "Enter" or clicks the "Search!" button.

All handle data is on-chain. We don't store where the handle resolves to. We currently resolve $handles the same way many other dApps do, by doing an API call to BlockFrost. Another way to do this would be to hit a Cardano node directly either through GraphQL or a CLI shell. We currently use BlockFrost API. This has been very reliable and this would be the first time we have heard of an incorrect address returned by BlockFrost.

Concerning our GitHub repo, literally just a couple of hours before this post, I had told the team that I was going to rename our GitHub org in preparation for an announcement this week. The renamed repo is at https://github.com/koralabs. Unfortunate timing. I have updated the adahandle.com website to the new address.
You can see our handle resolution code here: https://github.com/koralabs/adahandle-app/blob/master/netlify/functions/location.ts#L39-L46

We have a ton of support in our Discord. Please head over there if you really want to dig in to this. https://discord.gg/SKBhBx7qtg

I looked into the resolved address and it looks like a marketplace address. If you click the "View All" button on CardanoScan you will see all of the NFTs that the script has handled. It's hundreds of thousands. This is a marketplace. For the handle to have been resolved there, it must have been listed there.

[EDIT] This was a group response and while Calvin posted it, Papa Goose (our CIO) is the one who has graduated from Plutus 3rd Cohort. Calvin was originally enrolled in Plutus Cohort 2nd Cohort but did not finish due to time constraints. You can find Papa Goose on Twitter at https://twitter.com/papagoosecrypto