nostr:npub1gfdrrw9629qxwvwaa3vwnvzhtaqu2c5m9wf6vcwjnmdnhs7hl4jsux7gg6
I've never seen a deal that low, so that's a red flag. 
Second, always check the vendor site (https://www.microsoft.com/en-us/microsoft-365/buy/compare-all-microsoft-365-products)
If it's too good to be true, then your wallet is getting truly robbed.