When googling 'Euclid' is brings up this page which clearly has the wrong date of birth and death? As going onto to 'Euclid of Alexandria's Wiki page gives the correct dates.
Apologies if this is the wrong place for this.
It's because we don't have any really reliable sources for his birth, death, and the manner of his death. So we can only glean spotty information from his contemporaries. The best thing we've got is Proclus, who was writing centuries later (in the 5th century CE).