Bognor were playing well early on and took the lead on eight minutes. The Rocks capitalised on a play-on from the referee as Calvin Davies was fouled. Harrison Brook ran across the box before passing the ball back for Nathan Odokonyero who hit it. It deflected out to Jordy Mongoy who was waiting on the back post to slot in the opening goal.
Bognor brilliantly got their second on 17 minutes. A quick move saw Brook find space in the box and he spun his marker before smashing it low and in with his left foot.
Folkestone were level at 2-2, though, within five minutes. On 19 minutes David Smith crossed into the area and Adam Yusuff headed it into the turf and beyond Amadou Tangara. Amazingly, Jordan Wright got Invicta's equalising goal on 22 minutes. He received a square pass, composed himself and from 25 yards curled the ball at goal. It took a slight deflection as it dipped over Tangara and into the net.
It was an open, entertaining game but the Rocks could not regain the lead and nine minutes after the break Folkestone were ahead. The referee awarded a free-kick to the visitors as Joe Cook was deemed to have pulled the forward's shirt. Rocks switched off and a quick free-kick was passed out wide to Alfie Paxman. He sped on into space before crossing it onto the head of Smith, who diverted it high into the net.
As Bognor pushed for an equaliser. Invicta got a fourth 11 minutes from time through Smith - making it a disappointing outcome for Jack Pearce and Robbie Blake's men.
The Rocks are back at Nyewood Lane on Saturday against Waltham Abbey in the FA Trophy.