Here's how you change the email address you use for your Apple ID:
1. Go to https://appleid.apple.com and sign in.
2. In the Sign-In and Security section, choose Apple ID.
3. Enter the email address that you want to use as your Apple ID.
4. Choose Change Apple ID.
5. If you changed your Apple ID to a third-party email address, check your email for a verification code, then enter the code. Learn what to do if you didn't get the email. --> If you didn't receive your verification or reset email - Apple Support
6. If you use services like iCloud or Messages to share with friends and colleagues, sign in to those services with your updated Apple ID. --> What to do after you change your Apple ID or password - Apple Support
For more details, read the document: "Change your Apple ID" --> Change your Apple ID - Apple Support
I suspect you did not do it that way but instead created a new Apple account. Sign in using the old information and then change the address on that account. However, you won't be able to use the email address you just used to create a new account since that one is already irrevocably taken.
The other possibility is convoluted but it would be if you downloaded the aps with a different acount before you changed the email on the last one correctly. It needs to be logged into the account used to download the apps originally, whichever account that happens to be.