Why is my .htaccess redirect returning 200 instead of 301 during testing?

We have a Wordpress site, and it was changed from non-www to www several times due to some problems. The main issue is that Google indexed both versions which is not good. Finally we settled for www, and want to make sure non-www is not directly accesible from now on. Here is the code we used in .htaccess:

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

This mostly works except for some weird behaviour and mixed test results. When I test with Google Chrome incognito mode, I type https://theaksesuar.com and first it just connects and shows some distorted version of our site. When I refresh the page then it redirects to https://www.theaksesuar.com and displays the page correctly.
Redirect Checker and most other redirect checkers reports 200 instead of 301: https://www.redirect-checker.org
https://theaksesuar.com 200 OK

HTTP Headers
>>> https://theaksesuar.com

> --------------------------------------------
> 200 OK
> --------------------------------------------

Status: 200 OK
Code:   200
Server: openresty
Date:   Fri, 14 May 2021 07:50:51 GMT
Content-Type:   text/html; charset=UTF-8
Connection: close
Accept-Ranges:  bytes
Age:    153515
Cache-Control:  max-age=2592000
Content-Security-Policy:    upgrade-insecure-requests
Expires:    Fri, 11 Jun 2021 13:12:16 GMT
Last-Modified:  Wed, 12 May 2021 09:57:00 GMT
Strict-Transport-Security:  max-age=31536000; includeSubDomains
Vary:   Accept-Encoding, User-Agent
X-Backend:  local
X-Cache:    cached
X-Cache-Hit:    HIT
X-Cacheable:    YES
X-Content-Type-Options: nosniff
X-Xss-Protection:   1; mode=block

https://redirectdetective.com/ reports 301 fine. I will be glad if anyone can help.
Best Regards,