When a lonely 30-year old boss dreams about a mirror that shows you the way you’re going to die. He decides to find it but isn’t happy with what he sees, so he has to change his life so he can die happy. /Matilda

Suggestion: bring the story into the 21st century. He downloads a phone app that shows him how he's going to die. Or he gets a video embedded in an email with the same information. He dismisses it as a joke, spam, because he gets the same video every day until he changes.

Suggestion: bring the story into the 21st century. He downloads a phone app that shows him how he's going to die. Or he gets a video embedded in an email with the same information. He dismisses it as a joke, spam, because he gets the same video every day until he changes.

I find this interesting. A little bit "Christmas Carol" but with a twist. (A mirror instead of a ghost) I do think something needs to stand in his way.

How about something like this:
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"After discovering a mirror that can show your death. a lonely 30-year-old, vows to change his fate, but the new person he becomes ruffles his old friends and family."
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The idea would be that his "Friends" and "Family" use him: for money, for favors, to get out of trouble. Once he decides to change his fate he isn't Mr. "Old Reliable" anymore and they don't like that.

This would add some conflict.

Hope that helped, good luck with this!