Redirect entire subdirectory to a domain - .htaccess

Question

I am trying to redirect an entire subdirectory to our main domain.
Basically links like this:
https://garrysun.com/dev/ayurveda-products/categories/ayurvedic-ghee-clarified-butter?limit=15
https://garrysun.com/dev/
https://garrysun.com/dev/ayurveda-products/
Should all go to
https://garrysun.com/
We are using OpenCart 2.3.0.2
I have tried:
Options +FollowSymLinks
RewriteEngine On
RewriteCond %{REQUEST_URI} ^/dev/(.*)$
RewriteRule ^(.*) https://garrysun.com/ [R=301,NC]
and
RewriteRule ^dev/(.*)$ https://garrysun.com [R=301,NC,L]
But neither seems to work. What is the best .htaccess rule to make this work?

Answer 1

Inside /dev/.htaccess have this single rule:
Options +FollowSymLinks
RewriteEngine On
RewriteCond %{HTTP_HOST} ^(?:www\.)?garrysun\.com$ [NC]
RewriteRule ^ https://garrysun.com/? [R=301,L]
Your web server appears to be Nginx as per the response headers. For Nginx use this rule:
location ~ ^/dev/ {
return 301 https://garrysun.com/?;
}

Answer 2

I used this redirect:
Options +FollowSymLinks
RewriteEngine On
RewriteRule ^(.*)$ /$1 [R=301,L]
The problem is that if the page doesn't exist in the main website I get a 404 error.
For example:
This: https://garrysun.com/dev/777-oil-psoriasis
Becomes this: https://garrysun.com/777-oil-psoriasis
I get a 404 error because that page doesn't exist on the main site.
This works:
https://garrysun.com/dev/ayurveda-products/
Becomes:
https://garrysun.com/ayurveda-products/
because the new site has that page.