Hi @asd3r
This could possibly happen due to Your .htaccess blocking of hotlinking done by bing.
To exclude bing, possibly add both IP ranges used by bing, and also the bing URL.
A revised .htaccess may look like this:
<IfModule mod_rewrite.c>
# enable the rewrite engine
RewriteEngine on
# Example
RewriteCond %{REMOTE_ADDR} !^127\.0\.0\.1$
RewriteCond %{REMOTE_ADDR} !^<Server public IP>$
RewriteCond %{REMOTE_ADDR} !^<Server Private IP>$
RewriteCond %{REMOTE_ADDR} !^<Your Private IP 1>$
RewriteCond %{REMOTE_ADDR} !^<Your Private IP 2>$
RewriteCond %{REMOTE_ADDR} !^<AWS SSH IP>(.*)$
# Apple IPs
RewriteCond %{REMOTE_ADDR} !^17\.58(.*)$
RewriteCond %{REMOTE_ADDR} !^17\.121(.*)$
# Facebook IPs
RewriteCond %{REMOTE_ADDR} !^173\.252(.*)$
RewriteCond %{REMOTE_ADDR} !^69\.171(.*)$
# Twitter IPs
RewriteCond %{REMOTE_ADDR} !^103\.252\.112\.(.*)$
RewriteCond %{REMOTE_ADDR} !^103\.252\.113\.(.*)$
RewriteCond %{REMOTE_ADDR} !^103\.252\.114\.(.*)$
RewriteCond %{REMOTE_ADDR} !^103\.252\.115\.(.*)$
RewriteCond %{REMOTE_ADDR} !^104\.244\.40\.(.*)$
RewriteCond %{REMOTE_ADDR} !^185\.45\.5\.(.*)$
RewriteCond %{REMOTE_ADDR} !^185\.45\.6\.(.*)$
RewriteCond %{REMOTE_ADDR} !^185\.45\.7\.(.*)$
RewriteCond %{REMOTE_ADDR} !^188\.64\.(.*)$
RewriteCond %{REMOTE_ADDR} !^192\.133\.76\.(.*)$
RewriteCond %{REMOTE_ADDR} !^192\.133\.77\.(.*)$
RewriteCond %{REMOTE_ADDR} !^192\.133\.78\.(.*)$
RewriteCond %{REMOTE_ADDR} !^192\.133\.79\.(.*)$
RewriteCond %{REMOTE_ADDR} !^192\.44\.69\.(.*)$
RewriteCond %{REMOTE_ADDR} !^199\.16\.(.*)$
RewriteCond %{REMOTE_ADDR} !^199\.59\.(.*)$
RewriteCond %{REMOTE_ADDR} !^199\.96\.(.*)$
RewriteCond %{REMOTE_ADDR} !^199\.96\.(.*)$
RewriteCond %{REMOTE_ADDR} !^202\.160\.128\.(.*)$
RewriteCond %{REMOTE_ADDR} !^202\.160\.129\.(.*)$
RewriteCond %{REMOTE_ADDR} !^202\.160\.130\.(.*)$
RewriteCond %{REMOTE_ADDR} !^202\.160\.131\.(.*)$
RewriteCond %{REMOTE_ADDR} !^209\.237\.192\.(.*)$
RewriteCond %{REMOTE_ADDR} !^64\.63\.(.*)$
RewriteCond %{REMOTE_ADDR} !^69\.195\.(.*)$
# LinedIn IP
RewriteCond %{REMOTE_ADDR} !^108\.174\.2\.(.*)$
# Google IPs
RewriteCond %{REMOTE_ADDR} !^66\.249(.*)$
# Allow bing
RewriteCond %{REMOTE_ADDR} !^40\.77\.(.*)$
RewriteCond %{REMOTE_ADDR} !^157\.55\.(.*)$
RewriteCond %{REMOTE_ADDR} !^157\.56\.(.*)$
RewriteCond %{REMOTE_ADDR} !^13\.66(.*)$
RewriteCond %{REMOTE_ADDR} !^13\.67\.10\.(.*)$
RewriteCond %{REMOTE_ADDR} !^13\.69\.66\.24(.*)$
RewriteCond %{REMOTE_ADDR} !^13\.71\.172\.(.*)$
RewriteCond %{REMOTE_ADDR} !^139\.217\.52\.(.*)$
RewriteCond %{REMOTE_ADDR} !^191\.233\.204\.(.*)$
RewriteCond %{REMOTE_ADDR} !^20\.36\.108\.(.*)$
RewriteCond %{REMOTE_ADDR} !^20\.43\.120\.(.*)$
RewriteCond %{REMOTE_ADDR} !^207\.46\.13\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.77\.167\.(.*)$
RewriteCond %{REMOTE_ADDR} !^52\.167\.144\.(.*)$
RewriteCond %{REMOTE_ADDR} !^157\.55\.39\.(.*)$
RewriteCond %{REMOTE_ADDR} !^199\.30\.24\.(.*)$
RewriteCond %{REMOTE_ADDR} !^199\.30\.25\.(.*)$
RewriteCond %{REMOTE_ADDR} !^20\.125\.163\.(.*)$
RewriteCond %{REMOTE_ADDR} !^20\.74\.197\.(.*)$
RewriteCond %{REMOTE_ADDR} !^20\.79\.107\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.77\.139\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.77\.188\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.77\.189\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.77\.190\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.77\.191\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.77\.202\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.79\.131\.(.*)$
RewriteCond %{REMOTE_ADDR} !^40\.79\.186\.(.*)$
RewriteCond %{REMOTE_ADDR} !^51\.105\.67\.(.*)$
RewriteCond %{REMOTE_ADDR} !^52\.231\.148\.(.*)$
RewriteCond %{REMOTE_ADDR} !^65\.55\.210\.(.*)$
RewriteCond %{REMOTE_ADDR} !^72\.14\.(.*)$
# check that file exists
RewriteCond %{REQUEST_FILENAME} -f
# check for requested file types
# include additional file types here
RewriteCond %{REQUEST_FILENAME} \.(jpeg|JPEG|jpe|JPE|jpg|JPG|gif|GIF|png|PNG|mng|MNG|svg|SVG|IMG|img|webp|WEBP)$ [NC]
# allow blank referrer requests
RewriteCond %{HTTP_REFERER} !^$
# allow all requests from your domain
# edit the domain to match your own
RewriteCond %{HTTP_REFERER} !^https?://([^.]+\.)?example\. [NC]
# allow all requests from your ip address
# edit the ip address to match your own
# additional site access
# include additional sites here replace domain names and or
# remove unnecessary lines or add new lines for more sites
# RewriteCond %{HTTP_REFERER} !^https?://([^.]+\.)?domain_01\. [NC]
# search engine access
# include or remove search engines feed readers and other sites
RewriteCond %{HTTP_REFERER} !<your site>\. [NC]
RewriteCond %{HTTP_REFERER} !google\. [NC]
RewriteCond %{HTTP_REFERER} !yahoo\. [NC]
RewriteCond %{HTTP_REFERER} !twitter\. [NC]
RewriteCond %{HTTP_REFERER} !whatsapp\. [NC]
RewriteCond %{HTTP_REFERER} !facebook\. [NC]
RewriteCond %{HTTP_REFERER} !msn\. [NC]
RewriteCond %{HTTP_REFERER} !linkedin\. [NC]
RewriteCond %{HTTP_REFERER} !bing\. [NC]
RewriteCond %{HTTP_REFERER} !duckduckgo\. [NC]
# allow access to all requests for your anti hotlink image
# to serve an image instead of delivering a 403 error
# uncomment the next line and edit the path and file name
RewriteCond %{REQUEST_URI} !^/wpt-hotlinked-image-stub\.png$ [NC]
# deliver the hotlink image for all requests for the listed files
# protect additional file types by editing the list below
# if you are serving a file instead of a 403
# uncomment the next line and edit the path and file name
RewriteRule \.(jpeg|JPEG|jpe|JPE|jpg|JPG|gif|GIF|png|PNG|mng|MNG|svg|SVG|IMG|img)$ https://example.com/error-page/ [R,NC,L]
# return a 403 error when any of the following file types is requested
# you can protect additional file types by editing the list below
# RewriteRule \.(gif|jpe?g?|png)$ - [F,NC,L]
# close the module container
</ifModule>
