"I have no reason to keep texting with you, I know who you are."
It's a blunt and rather harsh way of saying that the speaker doesn't want to continue the conversation. The implied reason is that they are either no longer interested in the person or are upset with them. The statement also implies that they have discovered something about the other person that makes them uncomfortable or unwilling to continue the interaction.
Here's a breakdown:
* No tengo porque: This means "I have no reason to" or "There's no reason for me to".
* seguir texteando contigo: This means "keep texting with you".
* se Quien eres: This means "I know who you are".
The phrase suggests that the speaker knows something about the other person that makes them want to end the communication. It could be that they feel betrayed, deceived, or that the other person is not being genuine.