My 2013 Beetle Turbo has been experiencing an odd issue for about a year now. Mid-drive, it will suddenly beep very loudly 3 times and display the attached error code, which reads "Oil Pressure: Engine Off! Owner's manual!" while flashing the red oil light. (NOTE: The check engine light in the photo is unrelated; I got that issue taken care of after the pic was taken.) The first time this happened, I was on my way to a friend's house, where her dad checked my oil and said everything looked normal. I proceeded to experience the issue so I took it to both my normal mechanic and the dealer. They couldn't find anything wrong; temp and pressure readings appear normal. We replaced the sensor just in case that was the problem, but the issue still happens.

Some notes:
-This only happens after I've been driving 15+ minutes. It never happens on very short trips.
-NO other symptoms. Car is driving perfectly, no weird sounds/smells/sights, etc.
-I've had my oil changed in the interim and the issue still happens

Any ideas on what the heck this could be? It startles me to hear the loud beeping and anytime I'm driving a friend, I have to explain to them that nothing's wrong. I'm sick of hearing this damn beeping! Lol. Thanks so much in advance.