App Store on my phone shows wrong id and I can't fix it

This situation can happen if there are apps that are installed on the device that were installed under a different Apple ID, and they need updating.

The best way to resolve this is to delete the app requesting the update, and then download it again using the Apple ID that is signed in with the device.

You want to be careful that you do not lose any data, so be sure to check with the app developer to determine if removing the app will cause data loss.

These steps from "Delete apps on your iPhone, iPad, and iPod touch" [at: Delete apps on your iPhone, iPad, and iPod touch - Apple Support ] will help you remove the app:

How to delete an app

1. Touch and hold the app.

2. Tap Remove App [the "-" icon]. Remove App is the third option in the menu.

3. Tap Delete App, then tap Delete to confirm.

Keep in mind that some built-in Apple apps can't be deleted from your device, so you might not see the option to delete an app. Here’s a list of built-in Apple apps you can delete from your device [at: Delete built-in Apple apps from the Home Screen on your iOS 14 or later or iPadOS device or Apple Watch - Apple Support ]. If you can't delete an app that's not made by Apple, disable parental controls [see: Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support ], then try deleting the app again.

If you touch and hold an app from the Home Screen and the apps start to jiggle:

1. Tap the Remove icon in the upper-left corner of the app. (There's also an Add button in the top left corner of the screen and a Done button in the top right corner of the screen.)

2. Tap Delete App, then tap Delete to confirm.

3. Tap Done.

Once deleted, adding the app using the correct Apple ID should resolve the issue. See the article: Download apps and games on your iPhone or iPad [ Download apps and games on your iPhone or iPad - Apple Support ]

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This is modified slightly (for carry-over of linked documents) from a Community Specialist post: how do i get ride of a old id - Apple Community

Have you looked under Media & Purchases in Settings?

You say you "can't fix it" but what have you tried? If an app or feature on your device is not working or is restricted, it may have been disabled using Screen Time, or by an IT administrator if you are using a device owned by an employer or educational institution. See how to use Screen Time on an iPhone, iPad, or iPod touch by clicking here --> Use Screen Time on your iPhone, iPad, or iPod touch - Apple Support