Unable to sign back in App Store

Hi

Could someone please advise. I was unable to download any apps from the App Store so followed a Google suggestion to sign out of my Apple ID under SETTINGS - APP STORE. After doing this I am now unable to sign back in. When I enter my username and password it shows the loading symbol icon in the top right of the screen then just returns me to the same screen I have turned the phone off and on several times and even performed a 'soft reset' but still having the same problem. Furthest I have got is to be asked for my code used to unlock my phone but it then tells me 'verification failed' and returns me to the same screen yet again. I know that the details I've entered are correct. So frustrated with it. Any help will be greatly appreciated

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