I don't know about the ChargePoint, but some EVSE's like the GE DuraStation have the ability to have their charging rate dialed down if the panel it is connected to is incapable of supplying the maximum power it can deliver. It's done that way for safety reasons.
I would check the breaker that controls the EVSE. If it's less than 40 amps, that's why your car isn't charging at 7.2 kW. A 30 amp continuous draw would require a circuit rated for at least 37.5 amps, and breakers aren't available in that size, so you'd have to bump up to a 40 amp breaker and have wiring capable of that. If you're only getting 3.5 kW, assuming a 240 volt and not a 208 volt circuit, that's 14.6 amps you're drawing. If the breaker is 20 amps (meaning a maximum 15 amp safe continuous load), that would fully explain it.
If your breaker is at least 40 amps, the next place to check is the charging settings. On the 2015's, there is the ability to turn down the charging rate at the car itself, using the CarNet app. (My guess is this is a function of its European roots, where you can charge at home which is already 230 volts but likely not at the same amperage as you would get in the US.) Charging functions are done through the infotainment screen on later models, so check that and CarNet to see if that setting exists, if you have a 2016 or 2017 model.