Acti appears with a different name in Settings search

Customize the Action button · Go to the Settings app on your iPhone. · Tap Action Button. · To choose an action (like Silent Mode), swipe to the action you want ...

Use and customize the Action button on iPhone

To improve my understanding of the phenomenon, it would be highly beneficial if you could share a full screenshot (Do not crop it). Visual representations carry a greater impact than written descriptions.

Please remember that this is a public forum, so when attaching a screenshot, please avoid 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.

With the Action button on iPhone 16e and iPhone 15 Pro models, you can choose what you want this button to do, including opening the Camera app ..

Use the Action button, side button, and other controls on ...