RPI MAVlink - Connected but Getting Parameters 1

Hi all, I am currently using RPI 4 and APM 2.8 to connect via Mavlink. However, upon connecting with Mavlink on Mission Planner, I keep getting stuck at “Getting Params 1…” since forever.
I used the following code via SSH: mavproxy.py --master=/dev/ttyAMA0 --baudrate 57600 --out --aircraft MyCopter

Please help really appreciate it. Thanks in advance!