Service oil soon light flashes, car loses power 95 Park Avenue

What is your question?

Randomly while driving the service oil soon light will come briefly and the car will lose all power on my 95 Buick Park Avenue. The car will crank right back up whenever it loses power. This happens both before and after I got the oil changed. Any suggestions on what I can look because the shop I went to didn't help the situation?

What makes this problem better or worse?

Worse at higher speeds

How long has your 1995 Buick Park Avenue had this problem?

A couple of months