Horrible Internet speed

My download is FINE at 900Mbps+ it will occasionally drop to 400Mbps on a speed test but upload is constantly dropping from 10Mbps to 0.01Mbps and its leaving me unable to play FFXIV, Fortnite and even stream some youtube which is amazing at having 950Mbps download and youtube manages to buffer out of all things. While playing fortnite im having 30%+ packet loss on a WIRED connection

I already had a technician over to check outside and inside even swapped the modem which my net ran fine for 3 days now the problems have come back