I’m really sorry to hear about this, but as has already been mentioned by @breeron, Algorand (and pretty much most crypto currencies) is decentralized. This means that there is no “central one body” that can undo sometime.
Going forward I’d HIGHLY recommend some of the following when sending funds
- Always check the source you’re sending to. If you don’t know the person that well I’d recommend you e-mail them (to verify their domain) and have a call too if possible
- Never ever send a single large figure. Rather send a small amount first to ensure you have the correct address.
- If something sounds too good to be true, it almost always is. Stick to verified announcements (ie: ignore ALL Youtube or other streaming services) only.
Decentralisation is indeed fantastic to ensure no one party has absolute control of everyone’s money (unlike central banks do), but the downside is that there is no “undo” when issues like this arise.