Please tell me why this wont dock

[red mirage]

You prograde marker is very far away from you target marker. When docking you want progade, target and ship marker all at the same place

That works to some extent. But not that drastically

[plush ermine]

iirc there might be a mass limit for docking ports? try using a bigger docking port

[river dirge]

try and hold just short of the docking ports and make sure the prograde and target align exactly

then move in once your lined up