What is blowing up his phone?

"Blowing up his phone" is an expression used to describe excessive messages or phone calls sent to someone, often in a short amount of time. It may be used to describe persistent and aggressive attempts to contact someone. This expression is often used when someone is trying to get someone else's attention or attempting to get a response out of them. It is typically considered rude and intrusive behavior. It is important to respect other people's boundaries and limit your communication frequency to what is appropriate.