Redirect mistake need guide

Hi,

I've done a redirection mistake and want to cancel the redirection but fail. Been trying out for a day so coming to seek for your help

2 standalone site namely:
1. https://autoappointment.io/
2. https://app.autoappointment.io/
Initially my intention was to make https://app.autoappointment.io/'s front page to redirect to https://autoappointment.io/

What I've Done
1. Following this guide, I've made a hook element script and display to only front page https://imgur.com/a/RV3nc5M. After i tested this didn't meet what i want, then i removed and deleted the element
2. Next, i tried to add a snippet code like this https://imgur.com/a/TVJuiPV. After i tested this have some issues, then i removed and deleted the snippet code

Problem i facing now
1. When i visit the site home url https://app.autoappointment.io/ , it still redirected me back to https://autoappointment.io/ given i have removed and deleted the hook element and snippet code
2. When i visit this url https://app.autoappointment.io/sign-in , it still redirected me back to https://autoappointment.io/ given i have removed and deleted the hook element and snippet code
3. But when i visit other url such as https://app.autoappointment.io/sign-up or https://app.autoappointment.io/privacy-policy-2/, that was fine and no redirection happen. (Which is what i want)

Guide needed
1. Can you guide me on how to cancel the redirection https://app.autoappointment.io/ & https://app.autoappointment.io/sign-in to https://app.autoappointment.io/ ?
2. How to achieve redirect only https://app.autoappointment.io/'s front page (not other pages) to https://autoappointment.io/ ?

TIA