I have an iPhone 6 and when iOS 11 first came out, I was able to take Live Photos. Since the updates to 11.01 and 11.03, the Live Photos button has been removed. Why?

You don't since Live Photos was introduced later with iPhone SE and iPhone 6s/6s Plus releases and not before.

Read here from Apple : Take and edit Live Photos - Apple Support

You also need 3-D Touch to activate Live Photos once taken which iPhone 6 also do not have.

Tell us what you have in

Settings > General > About > Model > ???

If you have really an iPhone 6 then you do not have Live Photos, period.

iPhone 6 camera specs:

iSight Camera

• 8-megapixel iSight camera with 1.5µ pixels
• Autofocus with Focus Pixels
• ƒ/2.2 aperture
• Optical image stabilization (iPhone 6 Plus only)
• True Tone flash
• Five-element lens
• Hybrid IR filter
• Backside illumination sensor
• Sapphire crystal lens cover
• Auto image stabilization
• Auto HDR for photos
• Face detection
• Exposure control
• Panorama (up to 43 megapixels)
• Burst mode
• Tap to focus
• Photo geotagging
• Timer mode

Display

• Retina HD display
• 4.7-inch (diagonal) LED-backlit widescreen Multi‑Touch display with IPS technology
• 1334-by-750-pixel resolution at 326 ppi
• 1400:1 contrast ratio (typical)
• 500 cd/m2 max brightness (typical)
• Full sRGB standard
• Dual-domain pixels for wide viewing angles
• Fingerprint-resistant oleophobic coating on front
• Support for display of multiple languages and characters simultaneously
• Display Zoom
• Reachability

iPhone 6s Camera Specs:

Camera

• 12-megapixel camera
• Live Photos with stabilization
• Autofocus with Focus Pixels
• Optical image stabilization (iPhone 6s Plus only)
• True Tone flash
• Panorama (up to 63 megapixels)
• Auto HDR for photos
• Exposure control
• Burst mode
• Timer mode
• ƒ/2.2 aperture
• Five-element lens
• 5x digital zoom
• Hybrid IR filter
• Backside illumination sensor
• Sapphire crystal lens cover
• Auto image stabilization
• Local tone mapping
• Noise reduction
• Face detection
• Photo geotagging

Display

• Retina HD display with 3D Touch
• 4.7-inch (diagonal) widescreen LCD Multi-Touch display with IPS technology
• 1334-by-750-pixel resolution at 326 ppi
• 1400:1 contrast ratio (typical)
• 500 cd/m2 max brightness (typical)
• Full sRGB standard
• Dual-domain pixels for wide viewing angles
• Fingerprint-resistant oleophobic coating on front
• Support for display of multiple languages and characters simultaneously
• Display Zoom
• Reachability

There was never Live Photos on an iPhone 6.

Live Photos are available only on iPhone SE, 6s, 6s Plus, 7, 7 Plus, 8, 8 Plus and X

Read here

Live Photos is on by default on your iPhone 6s and later. If you want to take a still image instead, tap to turn off Live Photos. You can preserve your Camera settings so that Live Photos is always on or off. Go to Settings > Camera > Preserve Settings.

mvcp80 wrote:

not solved

My last post to you, thanks for the greenie.

There's nothing to solve since according to Apple specs, iPhone 6 do not have Live Photos option in the Camera app.

Happy hunting.

According to Apple: iPhone 6 do NOT have Live Photos. No matter what OP believes.

@mvcp80

Question answered, I am out of here.

I believe you're misremembering. The iPhone 6 has never been able to take Live Photos. People can send Live Photos to your iPhone 6. That may be the source of the confusion.

Go to Settings>General>About>Model. What does it say there?

mvcp80 wrote:

not solved

You are the only person who can mark a thread solved.