Photographer not responding

I booked a session for myself around 10 days ago and paid half of the money as a deposit. After I paid the deposit, the photographer hasn’t responded to any of my texts asking them about the location and logistics of our session. I have been texting them multiple times but there is no response. The session is in 4 days, what do I do now? I have been thinking of letting them know that if they don’t respond again by tomorrow I will be initiating a chargeback, is that inappropriate of me to do?