The keyboard on my iPhone is gone

There is a difference between a normal restart and a forced restart as described above. Therefore, it is not enough to just switch off your iPhone, you must do exactly as described above.

My last idea is that you contact Apple Support directly. They have the option to see and guide via your iPhone screen, this makes it somewhat easier to help, as it seems like a periodic error.

Contact Apple Support here:

Contact Apple for support and service - Apple Support

The keyboard cannot be deleted, and there will always be at least 1 active keyboard. Does it not work in all apps?

But try adding a new one and see if it comes up. Go to

Settings → General → Keyboards → Keyboards → Add New Keyboard...

Do you have, or have you had any Bluetooth accessories connected, for example a keyboard, if so - try deactivating Bluetooth here Settings → Bluetooth - restart your device afterwards.

Try doing a Forced Restart:

1. Press and quickly release Volume Up

2. Press and quickly release Volume Down

3. Press and hold the Side Button, the phone will restart. Release when you see the Apple Logo.

If this helps, try my advice from my first answer. Have you had a bluetooth keyboard connected?

cooktw Said:

"The keyboard on my iPhone is gone"

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Thank you for the screenshot.

Start with a Force Restart:

Go Here: Force Restart iPhone - Apple Support

It sounds like a glitch. Glad you got it working.