Why does Facebook show the wrong image when I share my website?

Facebook builds the preview from the og:image tag in your page's code. With no og:image it guesses, often picking a logo or footer icon. Set a 1200 x 630 share image in your SEO plugin, then use the Sharing Debugger's Scrape Again.

I changed the title but the old one still shows. Why?

Facebook, LinkedIn, WhatsApp and iMessage cache the preview card. Ask Facebook and LinkedIn to fetch again with the Sharing Debugger and Post Inspector; for messaging apps, sharing the address with ?v=2 on the end fetches a fresh card.

Why are there two og:image tags on my page?

Two tools are printing Open Graph tags, usually an SEO plugin and the theme or a social sharing plugin. Turn the option off in one of them so only one set remains.

More fixes

Your link shows the wrong picture or an old title when shared

You paste your website into Facebook, LinkedIn, WhatsApp or a text message and the preview card shows your logo cropped badly, a random photo from the footer, no picture at all, or a title you changed months ago. The card is not taken from the page you see. It is built from a few hidden og: tags in the page's code, and each platform keeps its own copy for days or weeks. Fix the tags, then make each platform fetch again.

What people see when the link is shared

facebook.com - new post

What the checks found

Why it happened (five minutes)

Read what the platforms read. Paste your address into Facebook's Sharing Debugger or LinkedIn's Post Inspector. Both show the title, description and image they found, plus any warnings. This is the test that matters: your own browser shows the page, not the card.
Is there an og:image at all? In the page source (Ctrl+U) search for og:image. With none, each platform guesses, and it often picks a logo, an icon or the first picture in the footer.
Two sets of tags? An SEO plugin (Yoast, Rank Math, All in One SEO) plus a theme or a "social share" plugin can each print their own og: tags. Platforms usually take the first one, which may be the stale one.
Tags right, card still old? Then it is the cache. Facebook and LinkedIn keep a copy of the card for about a week; WhatsApp and iMessage keep their own copy too. Nothing changes until they fetch again.
Image set but not shown? It is too small (under 200 by 200 pixels), too large (over 8 MB), on an http:// address, or a security plugin or Cloudflare rule turns the platform's fetcher away.

Fix it, safest first

Set one share image for the whole site. Yoast: SEO, Settings, Site basics, "Site image". Rank Math: Titles & Meta, Global Meta, "OpenGraph Thumbnail". Use a 1200 by 630 pixel JPG or PNG with the important part in the middle, so square crops still work.
Set it per page and post. In the editor, the SEO plugin's Social tab takes a title, description and image for that page. With nothing set, most plugins fall back to the featured image, so give every post one.
Remove the duplicate tags. If the page source shows two og:image lines, turn off the Open Graph or social option in the theme or the extra plugin and leave the SEO plugin in charge.
Clear your own caches, then view the page source again and check the new tags are there: a caching plugin or Cloudflare can keep serving the old code to the platforms.
Make each platform fetch again. Facebook Sharing Debugger: Scrape Again (twice for a new image, the first fetch can come back without it). LinkedIn Post Inspector: Inspect. WhatsApp and iMessage can hold the old card a while; sharing the address with ?v=2 on the end makes them fetch a fresh one.
Confirm. The debugger should show your title, description and image with no og:image warnings.

What you see, what it means, what it needs

What you see	What it means	Usual fix
Random photo, logo or icon in the card	No `og:image`, the platform guessed	Set a site image and a per-page social image
Old title or picture after you changed it	The platform's cached copy	Scrape Again / Inspect, or share with `?v=2`
Debugger shows two images or the wrong one	Two plugins or the theme print og: tags	Leave one in charge, switch the other off
No picture, warning about image size	Image under 200 px, over 8 MB, or an odd ratio	Upload a 1200 x 630 JPG or PNG
Debugger: "Could not retrieve data" or 403	A firewall or security plugin blocks the fetcher	Allow facebookexternalhit and LinkedInBot in the security rules
Fine on Facebook, wrong in texts	WhatsApp or iMessage cached an older card	Wait it out, or share the `?v=2` address

What not to do

Do not install another plugin "to fix sharing". More plugins printing tags is usually the cause, not the cure.
Do not delete and re-post the link over and over. The platform reuses its cached card until it fetches again.
Do not put a phone number or text near the edges of the share image. Each platform crops the card differently.

Most cases are one image setting and one Scrape Again. If the tags are printed twice, a firewall turns the fetchers away, or you would rather not touch it, that is what the box below is for. Related: wrong Google snippet, page title, changes not showing.