I can't import into keychain. I can't drop and drag. I have it turned on in iCloud. I tried creating a second keychain and it still doesn't work.

I am new. I inherited a half finished app. I successfully finished it in flipabit and got the app into Google Play with no problem. I am having a horrible time with Apple. The app had been rejected so many times by Apple, I decided that I would create a total new bundle.I have the Cert for signing, the mobile provision key, the Apple Distribution.cer , and an authorization key. I can't import any of them into keychain. I am thinking that that all these were created by someone else for the original app and I can't import any of mine, though that really doesn't make sense. Any and all ideas would be truly appreciated. I have been looking into upworkk to have someone do this for me but I am wondering how in the world they could do that.

Apple Connect seems to be stuck on the rejected version. I inherited this app and made the changes needed for improved functionality. I was built in Flipabit. I created the ipa in there. The new build looks great in Test Flight. I used Transporter to deliver the app. I have changed version in Apple Connect. I deleted the old build using the minus sign. I hit save. However the images displaying are from the old version and I worry because I tried this before and it was rejected again using the old version and build even though I changed them. My problem with creating a whole new app is Flipabit gives and error when trying to build that the provisioning profile even though the ID matches the new bundle ID. I have literally spent about 20 hours on this trying everything over and over. I believe that is called insanity. I am praying there is someone to help me. Thank you in advance.