Stuck pneumatic cylinder

I've just received a baomain pneumatic cylinder from amazon (50 mm bore 100 mm stroke). When I tried to move it back and forth by hand, it wouldn't budge. Ive never used pneumatic cylinders for robotics before, but I'm fairly certain that they should be movable by hand. Does anyone know the awnser to this issue, or if it is even an issue?

• What type of cylinder? Can you edit your question to add a link to the cylinder on Amazon? – sempaiscuba May 6 at 23:21
• did you take out the plugs from the ports? ..... upvote for not assuming that there is an issue – jsotola May 7 at 1:08
• this site shows red plugs in some of the ports .... baomain.com/cylinder#! – jsotola May 7 at 1:17

You also have to take into account the shaft diameter when calculating acting surface area - the "extend" action uses the full bore diameter, but the "retract" action can only act on the surface area that is exposed, which is the area of the full bore diameter minus the area of the shaft diameter - $$A = \pi \left(\left(r_{bore}\right)^2 - \left(r_{shaft}\right)^2\right)$$.