Sometimes washer won't move from fill to agitate

My top loading washing will fill with water. Sometimes it will run without a problem. Other times it will stop once it fills. No strange sounds or smells. It’s like someone pressed pause. If I manually move the dial, it will agitate and run the rest of the cycle. Has happened in regular and casual load settings (strength of agitation). Most fixes seem to be if the agitator doesn’t work at all so I don’t know what to do. Any ideas?