>>528694059
You would have to have another email account. Salted emails don't work on Hoyo games anymore. You then have to make a new account and do everything again. I wouldn't bother. Keep doing the story and rolling.
Have you got a standard character from rolling on the Yixuan banner? If so your next 5 star is guaranteed to be her.
Don't save your standard banner signals. Spend them.
Getting any A ranks gives you residual signal which you can exchange in the shop for limited banner rolls. You can get residual signal by getting A ranks on the standard or limited banner.
There's plenty of easy polychromes to get by finding bangboo around the maps and fixing them, doing the agent tutorials and don't forget to do your first time check in on the hoyolab website to get polychromes.
Have you used all the current gacha codes? Like ZZZ20SIMI
ABZVGEWK3O
ZZZ20NEWSEASON
ZZZ2NDSEASON
ZENLESSGIFT
Have you bought the discount limited signals from the fading signal shop which you can buy for currency you get just by rolling on any banner?
Check the residual signal page and the fading signal page to see if you can buy limited signals (encrypted master tapes).