Connection issues

I saw a post recently that i now can’t find i think it was on instagram that had a list of tips for each platform (i’m on Xbox) regarding connectivity issues or lag. I used to use a Lan cable which had my ping at like 10ps which is really good but it suddenly started to be that going into a game but then get ridiculous speed up lag like upwards of 1000 ping in game for a few seconds like every minute or so, so i switched back to wifi where my connection ranges from like 20-50 ping depending on who im playing. If anyone could help would really like to return to using my cable but that speed up lag is unbearable and costs me a lot of games.