Hello,
Thank you for your query and we are so sorry about the trouble this must have caused.
It is a pretty common thing with Google these days. It happens with 70% of the results and we even have a KB dedicated to this problem and a few solutions we recommend:
https://rankmath.com/kb/different-meta-title-and-description/
Please check the KB and you will understand the reasons Google does this.
Google has made some changes to their algorithm which automatically changes the titles, discarding the one you have set in your SEO title meta tag. This happens regardless of the SEO plugin you are using. We have covered this Google update here:
https://rankmath.com/google-update/google-title-rewrite-update/
Hope that helps and please do not hesitate to let us know if you need our assistance with anything else.
Ok, so.. I just need to follow the instructions in that article?
Also, how come when I type a keyword related to my website in google search, the website only shows up on my computer. But when I try to search it up on other devices, it doesn’t show up at all??
Hello,
Yes, if you follow that article, it will guide you with optimizing your website’s meta to make sure Google will utilize it for the Google Search Page.
We checked that our plugin is indeed adding the correct meta so its up to Google to make use of that or, you can optimize it more for the search intent:

Also, how come when I type a keyword related to my website in google search, the website only shows up on my computer. But when I try to search it up on other devices, it doesn’t show up at all??
One of the possible reasons for this is that Google tailors search results based on individual preferences, search history, and location, which may affect how your website ranks on different devices.
Also, Google may prioritize websites with local relevance, resulting in differing search rankings based on location and device.
Hope that helps and please do not hesitate to let us know if you need my assistance with anything else.
Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.