How to solve the high LCP issues?

The pagespeed values of the site are already pretty good, I would even say above average. You can be proud and happy about this, because it is already adding value to the site.

The LCP may be somewhat unfavorable, but it doesn’t carry too much weight. You also have to consider how it is recorded: over a longer period of time only from devices that access the site with Google software and that allow this recording. It will not change into something better in the short term, if at all. However, it can also have this value for historical reasons, as it is valid for a certain period of time. If you have made the optimizations recently, it could be that they have not yet had an effect on the value. Just wait a little longer.

Alternatively, you can of course also contact the support team for the optimization plugin you are using: https://wp-rocket.me/support/ – as this is a commercial product, they cannot help you further in this forum.

You could also (possibly again) take a look at this article on general optimizations: https://developer.www.ads-software.com/advanced-administration/performance/optimization/

To improve your website’s LCP, focus on optimizing images, minifying code, deferring non-critical resources, leveraging browser caching, and considering a CDN. Resize and compress images, minify JavaScript and CSS, and defer non-critical resources to load after the initial page load. Utilize browser caching and a CDN to store and deliver website content efficiently. These strategies will help enhance your website’s loading speed and overall performance.