If one of your Facebook friends claims that he/she sent a text and received a free Target gift card in exchange, it's a hoax. The simple lesson here is that if it looks too good to be true, it probably is.
According to an article on Goodhousekeeping.com, the Facebook post appears to come from someone you know, and it may look like this:
This is a phishing scam.
The rule of thumb to avoid being scammed is this: Don't click links or open attachments in unexpected or unusual messages. Always verify before clicking. Other red flags are messages urging you to act now, messages asking for money, and anything offering something for nothing.
Want to stay safe online? Be careful what you click. When in doubt, verify. It's as simple as that.
For more information, see https://www.goodhousekeeping.com/life/money/a20952055/target-gift-card-scam/.