After the safety car was deployed, Hamilton endured a frustrating race as he seemed to struggle to get past the Haas of Kevin Magnussen.
After an intense battle with Magnussen and Yuki Tsunoda, Hamilton overtook the RB on the final lap as he looked to have secured a point for Mercedes in eighth.
Hamilton handed 20-second penalty
However, the seven-time champion was handed a drive-through penalty after the race for speeding in the pitlane.
As it was given after the race, it was converted to a 20-second time penalty and demoted Hamilton to P16, handing Tsunoda the final point in a double points finish for RB.
This incident is not the first time Hamilton has been subject to investigation by the FIA in Miami.
The Brit was summoned to the stewards after the Sprint Qualifying after his pit crew were seen to service Hamilton without their helmets on, but no further action was taken.