I use trumpet to send text messages to my ex-boyfriend. He always asks me who I am and calls me. What should I do?

When you texted your ex-boyfriend, you were still thinking about him. If so, you can boldly answer his phone, communicate with him and understand each other's situation. If he still misses you, you can also tell him what you think. If you want to make it up, you can pursue it boldly. If you don't want to make up, there is no need to entangle too much. Let bygones be bygones.