STM32H755 Buffer to DMA to UART3 Setup, not entering interrupt maybe

I am following the tutorial for memory to peripheral (UART) from Digikey https://www.digikey.com/en/maker/projects/getting-started-with-stm32-working-with-adc-and-dma/f5009db3a3ed4370acaf545a3370c30c

starting @ 6:00 and ending @ 10:00 minutes in

The tutorial involves a custom callback function but I don't think that's the issue. I'm guessing it's somewhere in maybe the setup for the interrupts or which exact register I'm using. I'll attach my .ioc file and main.c for the m7 core.