Not receiving advertised speeds

I recently upped my internet service to the 600mbps package. I have a brand new modem and brand new router both rated for 1GB service, and I just re-ran a new coax cable from my side of the service entrance to the modem (it was previously about 200’ long, and spliced at least once). I am still getting no more than 100mbps on my router speed test and even worse on my laptop, phone and gaming console (tested both hardwired and WiFi). I have tried every troubleshooting step or option available and I’m pretty convinced that it’s the incoming line from the pole. I’m hoping to have a tech come out to my house and take a look and hopefully fix it so that I’m not paying for something that I’m not actually getting.