Skate3

Hi I dont know if anybody can help. Skate3 was running great on my xbox series x , dead smooth most of the time , I added someone that got a bit shirty n a day later my whole game online mainly , runs rubbish, laggy and makes others lag if they go online with me. I cant even drop in without it throwing me sideways or off my board. Thinking it was the Internet I looked at that n dont think its that. Deleted account, made a new one , reset whole xbox , not that either. Every time without fail I switch it on , now with an xbox one instead. Its the same. Lag. Permanently. Any ideas why ? Pls 🙏