Woocommerce Checkout Slow

I’m Marcos!
I’m from Brazil and I’m using the google translator to show how I found the solution!

My woocommerce checkout was loading very slowly and when the click clicked to place the order it took more than 20 seconds.

I tried to use this code in the function file and it didn’t help, the checkout of woocommerce continued to be slow.
add_filter( ‘woocommerce_defer_transactional_emails’, ‘__return_true’ );

I had to disable all plugins and activate 1 by 1 until I found the ones that were ruining the checkout of woocommerce.

After several days of testing, I found a solution, now the checkout loads 3x faster and when the customer presses the button to do the fart it loads super fast …

Always check wc-ajax=checkout to perform the operation in 3 to 5 seconds!

Jetpack deactivated and left it for backup only.
Disabled: Manage Notification E-mails
Disabled: Ninja Checkout
Disabled: Query Monitor
Disabled: WP Fastest Cache

All cited plugins that I deactivated were up to date 04/12/2020.