Pls let us know which code example you are using or you could also attach your project.
Also, elaborate on your issue so that we can reproduce it at our end.
Please find the project in the attachment for your reference.
Capsense buttons are working fine while UART interrupt is never triggered when I send some data over UART (using Putty).
You seem to not have not checked "Rx FIFO not empty" in UART SCB component configurator window. (UART Advanced tab)
Pls enable the "Rx FIFO not empty" interrupt source and check if ISR is triggered.