Can’t share Instagram story to Facebook
Instagram stories to Facebook not working
When sharing a story on Instagram, the share to Facebook option has disappeared? Do not panic, see below how to get it back in a few simple steps.
In short, go to Settings > Linked Accounts > Facebook > log in, and reconnect to the Facebook account.
This usually happens after Instagram has lost connection with Facebook, for example in the case of a password change, a switch from an account to another on the same Instagram app, a change of connection or country, and in general a need to reconnect to the Facebook account.
Where Can I FLY? Instagram page

Starting from Instagram, open the settings, which are accessible from Instagram account detail screen by tapping the top right icon, which contains three parallel lines.

Instagram not posting to Facebook 2018
Here, the account settings offers all possible menus, including the one that matters to reconnect the Facebook account: linked accounts menu – tap on it to enter.

Now, all external sharing accounts used by the Instagram account are listed. At the moment, the possible services that can be used are Facebook, Twitter, Tumblr, Ameba, and OK.ru.
Even if the right account is shown here, it might be that it has been disconnected from the Instagram account. This can happen in several cases, the most common one, when administering more than one account on the same phone, being switching between accounts.
There is actually no way to get the connection back by default when switching accounts, and it happens, especially for Facebook business page sharing, that it must be reconnected after every account switch.
Tap on the Facebook account to reconnect it.
Where Can I FLY? Facebook page

No option to share Instagram story to Facebook
Even if the Facebook account name was shown on the previous screen, we can see here that it has been disconnected from the Instagram account, as the option to login is offered to change where it is possible to share.

Simply tap on the log in option, and in most cases, after some exchange between Instagram and Facebook, which are materialized by a loading animation, the Facebook page name will appear again.
There is likely no need to even enter the Facebook password again, nor to select the page to use, but simply to tap on the log in link, and wait for the re-connection.
The option to unlink a Facebook account from Instagram is also here.

Share your story to Facebook not showing
And that’s it! Now, go back to the latest Instagram story that has been posted on the account, and the share to Facebook icon should be back here, displayed as not shared to Facebook yet, as the icon background is transparent.
International SPA and Web consulting on Facebook

Tap on the Facebook icon, after what a popup share to Facebook story will appear.
Either tap on the button to perform the share to Facebook instantaneously, or tap outside of the box to cancel the action and not share the story.

Instagram Facebook share story disappeared
That’s it ! A message box will confirm the share to Facebook, if successful, and the Facebook sharing icon will have switched colors, showing now a white background and a transparent icon.

The share to Facebook icon might disappear regularly, and especially when switching accounts, for example going from a business account back to the personal account, and back again to the business account.
Every time the action is performed, it might be necessary to reconnect to the Facebook account in order to be able to share the story.
Instagram won’t share to Facebook story
Pay attention, sometimes, after switching accounts, and sharing a new story on Instagram with a Facebook share, it might be possible that it will end up on the Facebook account story, instead of the connected business page story.
I that case, it is necessary to first go in Settings > Linked Accounts > Facebook > log in, to ensure that the story will be properly shared.