Unable to navigate my eBay had to remove app and try to reinstall it. App didn’t upload to my phone

[pmm224]

I have to go to the App Store every time I want to access my eBay account.  Today I was unable to navigate through my eBay account as nothing worked.  Tried for hours.  I deleted the app but could not find any way to upload it in the App Store.  I now have to go to the App Store every time I want to access my account.  How do I retrieve the app.