How to get over some coworkers not liking me for some reason?

For some reason at work this coworker randomly went from being cool with me to treating me like I talked bad about him to a manager which I didn’t because i can’t even remember his name in the first place. But it’s getting me paranoid because last thing I want is someone to despise me at work. Like I can manage dealing with someone not trusting me with tasks but I don't know about this
How to get over some coworkers not liking me for some reason?
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