AC1200 Slow 5g speeds

Hi folks. I just purchased an ASUS AC1200 router to replace a TP Link router that had given out on the 2.4ghz side.

I set it up last night however I cannot get a download speed any higher than 60mbps with the 5g connection. I’ve cycled through all the connections to no avail. I have a 300mbps connection through Xfinity and my TP Link router currently broadcasts a 215mbps download speed over its 5g connection.

Any suggestions in how I can improve the speed or should I just ship it back?...

AC1200 Slow 5g speeds