Think about learning to drive a car. You come to an intersection, and you check
very carefully to make sure that there aren't any other cars moving in a way that you have to avoid. Then you proceed.
After a while, you don't drive that way. While you should still maintain caution, you just see the other cars. You are now a better driver, not a worse one.
In the same way, you grow as an engineer partly as you grow the number of situations that you can just "pattern match" on. It doesn't mean that your logic is somehow failing you! Instead, it means that when you see that situation, you "just know" how to solve it (typically, by seeing similar situations a few times). The logic still works for the situations you don't know how to "just see" the solution to.
If you're solving all your problems on autopilot, it means you're ready to step up to harder problems.
And, a caveat. "Autopilot" can produce wrong results from time to time. It's worth taking a bit of time to think through whether the solution is actually right (the more important the problem, the more time is appropriate).