Hi Nunofyabusiness,
Thanks for posting here in Apple Support Communities. Have you tried changing the Lock Screen on your iPhone? If so, does the issue remain the same? You can see how to customize your Lock Screen using this article as it may help to resolve your issue. See: Change the wallpaper on your iPhone
Customize a Lock Screen wallpaper with filters, widgets, and styles
In the Settings app, tap Wallpaper.
Under the preview of your Lock Screen, tap Customize.
Tap Customize Current Wallpaper or Add New Wallpaper and select a wallpaper.
Before you tap Done on the wallpaper, make your customizations.
To choose a font and text color, tap on the time.
To add or remove widgets — like Calendar, Clock, Weather, Fitness, or Reminders — tap on the boxes above or below the time.
To apply photo styles — like Black & White, Duotone, or Color Wash — swipe left or right.
To crop and move your photo, pinch and drag your photo.
To select wallpaper options, tap the More button. Perspective Zoom moves the wallpaper as you tilt your screen. Depth Effect enables layering with the subject of your photo.*
Kind regards.