Slide occasionally not closing

I was wondering if anyone else had a similar issue:

When I first got my LCP, I went straight to the range and, while shooting, had a few instances where the slide would not go completely forward, hanging up about 1/2 cm from closing.

After a cleaning/lubricating, the problem went away at the range.

Since then, I've been dry firing with a snap cap, and when retracting the slide a bit to...not sure what it's called, cock the hammer/load the spring/???...it will sometimes hang at the same spot.

I DO NOT experience the same thing if the chamber is empty.

I haven't analyzed it super closely (a slight tap on the slide will nudge it forward) so I'm not sure what interlock is getting hung up, so I'm wondering if anyone else has seen this, and if they've figured out the cause.

To note, the sticking point is just where the barrel makes its final pop up into place when the slide closes...