Telling the truth where it may create a problem
	
	
		I am working for a german company online. I was waiting here for him for two days. I sent several mails.  But he did not reply.  Also not came online. I was waiting and waiting.  Today we have a conversation but he totally denies that he was not online rather he is blaming me constantly that I did not come online that two days I was waiting for him.  So in this situation 
1. How can I justify that I am truthful?  Submitting the emails?(it may make him angry)
2.  What Islam say about telling the truth where it may arise problem?
Kindly give me a solution to resolve my crisis.