Are you sure it's not just your internet being shitty? IMO, you should not submit any score that can restrict you in 1 week or so, just play unranked maps. And PP farming is boring af. I stopped pp farming after 4 or 5 of my 3-digit accounts got restricted.
But I doubt you came here to listen to my rambling lol.
Firstly, I think you should properly follow all steps.
Any errors popup when you submit your score? You should at least have a screenshot or something so that people can help you troubleshoot.