Hello. Welcome ot Just Answer. Pleas allow me to assist you. This sounds like you have a battery or battery power condition. Since your clock reset to 12:00, thsi means that the dashboard lost all power. That rules out anything with the key side of the electrical system. When you have an intermittent issue like this, we usually would expect tot find one (or a combination of ) the following:
Loose plate/bad internal contact inside the battery
Loose battery post (positive or negative
Corrosion at the battery posts where the terminals connect
Corrosion inside the wire fo the battery cables (under the nylon insulation jacket)
Poor connection of the negative battery cable to the body metal
Poor connection at the fuse panel where the Positive battery wire attaches.
More often than not, either the battery, the terminals/posts, cables and battery ground connection is the most common.
The first thing I would do is see if the battery terminal ends are loose. Then check for corrosion on the posts themselves. If all that looks good, check the negative cable connection at the body ground point. If all this looks good, and the posts are nto physically loose on the battery, you may need a battery.