Problem with rest api

I have a WordPress page at domain “smartticket.com.bo” and a Rest API at “www.smartticket.com.bo/api” developed with Codeigniter.
We don’t use https.
After installin WP Fastest Cache, ir changed the .htaccess file and now when I try to use the Rest API, I receive the message:
{
“status”: false,
“error”: “Unknown method”
}
Before the changed .htaccess, I can access API with “https://www.smartticket.com.bo/…”, and after the changes, the only way is with “https://smartticket.com.bo/…”

I have a mobile app that is working with “https://www.smartticket.com.bo/…”.
Please help me to modify the .htaccess to use the cache and my API.
Regards