Continuously get the same errors when trying to publish application
I am a new application developer and my main issue is publishing it to the App Store! After hours of frustration I somehow managed to publish my application back in December, but now I have come out with an update and it seems that with every step I take, I take 3 steps back.
My issues: I have made countless different modifications to Provisioning Profiles and certificates to attempt to solve the errors that keep coming up. I have deleted everything and started over numerous times, each time being very cautious about my steps.
My first error was the ITMS-4238 in which there was an error / duplication in the Bundle ID.
Since I couldn't resolve the issue I decided to start from scratch, deleting everything and restarting yet now I've run into another error when attempting to Sign the App from a newly created Provisioning Profile. Upon selection the error "Could not code sign because there is no developer identity matching the selected provisioning profile" appears.
Any insight / assistance is greatly appreciated for I have hit a wall.
Please mention any / all possible errors which I may have made based on my steps below.
On Apple Dev Center -
1. Create Certificate (have tried both the emailed version / save to disk) under appropriate info.
2. Open certificate / upload to Keychain Access
3. Created correct App ID
4. Create correct provisioning profile and double click .mobileprovision to open in Xcode (recently updated)
5. Opened preference in Xcode > View Details > Refresh
6. Generate App on GS
7. Sign App - Select Provisioning Profile created
8. Receive ERROR "Could not code sign because there is no developer identity matching the selected provisioning profile."
Please help
Thanks