Ps4 Disc drive mechanism

Good afternoon, sometimes my ps4 have troubles reading discs, if I gently hit the top of the console while trying to read the disc it works. I opened recently and I notice the barrier that pops up when a disc is inserted is not fully up, causing the disc to get stuck not going all the way, I was wondering if it is a mechanism problem from the drive or the lector lens. cheers. the white plastic on the left side of the mechanism doesnt seems to go all the way.