Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Microchip Technology/ATSAMV71J20/MLB/ACTL#0x0
MPB=SINGLE_PACKET
AHB Control Register
Software Clear Enable
AHB Interrupt Mux Enable
DMA Mode
DMA Packet Buffering Mode
0 (SINGLE_PACKET): Single-packet mode
1 (MULTIPLE_PACKET): Multiple-packet mode
https://github.com/cmsis-svd/cmsis-svd-data