You actually sold that put, that's why it shows you received a $12 credit and indicates that you'd have to buy the option back to close out the position. Holding until expiration gets you that extra dollar in premium if the option expires worthless. Buying it back for a dollar closes out your position, releases collateral, and eliminates tail risk (if USO drops below $12 before 6/5 you could get assigned 12 shares at $12).
Many option sellers take profits before max gain is achieved because there's often something better to be done with the buying power that's tied up in an option that has already achieved the bulk of its potential.
All the 12's in this scenario are a fun coincidence, you happened to sell the option for $12, the strike was $1.5 but that's equivalent to a $12 strike post-split because 1.5 x 8 = 12. It's 12 shares that you'd be assigned because 100/8 = 12.5 and they convert the fractional shares to cash.