Who’s Telling the Truth?
It is known only one character is telling the truth. Mr. April says that Mr. May tells lies. Mr. May says that Mr. June tells lies. Mr. June says that both Mr. April and Mr. May tell lies.Who is telling the truth? 
Hint: Consider whether each character in turn is telling the truth; you will end up with only one possible solution.
Also Try: Who is the thief?
AnswerMr. May is telling the truth.

I don’t understand this.puzzle.
The reasoning in this riddle dosent hold up. Example: If Mr. June is telling the truth, while saying the other to lie, couldnt he be the man we are looking for?
If you consider that Mr. June is telling truth that means other 2 are also saying truth so all 3 would be saying truth but riddle says only 1 is saying truth which means June will always be lying. He says both of other lies which is lie as one of those is saying truth. Now, only question remains is which one.