Can’t access iPhone wallpapers through Lock Screen

Even if you press and hold the screen for 1-2 seconds?

Should be this case, have you tried a "forced" restart of your device using these instructions?: Put it on charge for at least half an hour, then, keeping it plugged in, use these gestures:

Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the side (power) button. Only when the Apple logo appears (it might take 10-20 seconds), release that button (ignore all other screens that might appear, the one with the "slider" to turn the device off included).

If the issue still persists, since you device is covered by warranty, I suggest that you make an appointment (*) and have your device inspected at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> https://locate.apple.com/choose-country-region . After checking it out, they'll give you all the available options.

Regards

Giulio

(*) You can do it:

• Online:--> Genius Bar Reservation and Apple Support Options - Apple;
• Contacting a local Apple Store or AASP among the list provided above;
• Using the "Apple Store" app, available and downloadable from AppStore.

We, just users like you, cannot diagnose that kind of issue remotely, sorry.

As already suggested, if you already tried (to no avail) the steps provided in my previous reply, contact Apple Support directly, using this link:--> Contact Apple for support and service (they have tools to run remote diagnostics), or visit an Apple Store or AASP.

Regards

Giulio