I have 3 domains pointing to my hosting. The "main.com" one uses an http redirect using the <meta> tag pointing to its own subdirectory. The "domain2.com" site redirect has worked for a long time. I just added the "domain1.com" redirect to the .htaccess file in the htdocs directory but it is not working - it still redirects the same as the "main.com" one.
Here is my .htaccess file. Where is my mistake? Thanks!

ErrorDocument 400 "<body><h1>Bad request!</h1><body>
ErrorDocument 401 "<body><h1>Authorization required!</h1><body>
ErrorDocument 403 "<body><h1>Forbidden!</h1><body>
ErrorDocument 404 "<body><h1>Page not found!</h1><body>
ErrorDocument 500 "<body><h1>Server error!</h1><body>

RewriteEngine On
Options +FollowSymlinks
RewriteBase /

RewriteEngine On
RewriteCond %{HTTP_HOST} !^www\.
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [R=301,L]

RewriteCond %{HTTP_HOST} domain2.com
RewriteCond %{REQUEST_URI} !other_websites/domain2/
RewriteRule ^(.*)$ other_websites/domain2/$1 [L]

RewriteCond %{HTTP_HOST} domain1.com
RewriteCond %{REQUEST_URI} !other_websites/domain1/
RewriteRule ^(.*)$ other_websites/domain1/$1 [L]