Circle with grid

Are you referring to an icon as shown in the pic below?

You see this ...

If you had changed any of the following recently.

• Apple ID
• Apple ID Country
• App Store Country
• App is offloaded and you have downloaded the app and the developer does not provide any more support the app in the App
• Data transferred from another iPhone. When you transfer between iOS devices only the app data gets transferred the app needs to be downloaded from the App Store.

Based on your image posted, it's possible that the app icon you're seeing on your iPhone with a mesh-like texture is actually a placeholder icon that appears when the original app icon cannot be displayed properly.

This can happen for a variety of reasons, such as when the app has been removed from the App Store or when the app has lost its connection to the App Library. In some cases, this can also happen when there is a problem with the app's icon file or when the app is no longer supported by the developer.

If you suspect that the app is no longer supported or has been removed from the App Store, you can try searching for the app in the App Store to confirm whether it is still available. If you cannot find the app, it is possible that the developer has discontinued support for it.

Finally, it's possible that the mesh-like icon you're seeing is related to device compatibility. Some apps may not be optimized for all iPhone models or iOS versions, which can cause them to display incorrectly. If this is the case, you might try contacting the app developer for support or looking for an alternative app that is compatible with your device.

Alternatively, if you believe that the problem is related to a lost link to the App Library, you can try resetting your iPhone's home screen layout. To do this, go to Settings > General > Reset > Reset Home Screen Layout. This will reset your home screen layout to its default settings, which should fix any problems with missing app icons or links to the App Library. However, please note that this will also remove any custom app layouts or folders that you have created on your home screen.

You may also try...

• Restart the device. That's it.
• Still not solved --> Force restart iPhone - Apple Support

For enhanced comprehension of the phenomenon, it would greatly benefit if you could kindly repost using a screenshot. Visual representations hold more impact than mere words.

Please bear in mind that this is a public forum, and when attaching a screenshot, refrain from including any personal credentials such as IP addresses, card details, email IDs, Apple IDs, IMEI numbers, serial numbers, phone numbers, order IDs, or any identifiable location information if you are sharing a map.

With the limited information that you have provided, It is hard to even guess the problems faced by you. 

You may get faster and better responses to your query by --> Writing an effective Apple Support Commun… - Apple ...

Please re-post with detail so that someone else can help.