Can't change my website title in SERP.

Hello! I have a problem.
I have low CTR in the SERP because of my old website title.

It has the following structure:

WEBSITE NAME + Keyword + Keyword + Keyword

Long time ago I changed my title in Yoast SEO to be

Keyword + Keyword + Keyword + WEBSITE NAME.

But the title is still old and people are not clicking on it that much because the keyword they are looking for is hidden after the website name. I know that Google is not obligated to take the Title from the website title tag, but is there any way to change it? I changed it in Yoast SEO very long time ago, I also checked whether it changed in the HTML code of the website. But Google still doesn't pick up the new title and my CTR is suffering a lot because of this.

If you are sure that you've changed your title in HTML, there is nothing else to do as wait for Google to index that. There is plenty of serp checkers services for free that will let you check how your site will be looking in the google search results page.

Sometimes it takes time to fetch & Crawl webpages.

check that you have properly changed the title in yoast, sometimes yoast takes title from other elements. google should not add your website at first unless you have asked them to, however you can't do much in this case and google will do it itself if all you have done is correct at your end.

Yes, i did everything correctly in the Yoast. Don't see how it is possible to do it in Yoast incorrectly.
I changed the title in Yoast 4 month ago, so i don't think that the crawling is the problem. I update my website often so Google crawles it often.

Should i completely delete the title in Yoast to try reset the title? It really hurts my CTR. I had only 12% CTR when I was on the first place is SERP for my keyword. This is because of the bad title.