@georgiaSIO It sounds like you either have a poorly created Custom Content or it is broken after the new game patches/updates.
Please check with your Custom Content creator to see if there is an update.
In the mean time, please remove the Custom Content that creates the eyelashes and then delete the localthumbcache.package file in your 'The Sims 4' folder. Once you have the new, updated Custom Content you can re-add it.
@georgiaSIO You will have to remove the whole package. I cannot advise you on if there is any manner to adjust the person's CC yourself and what issues that may cause. If the eyelashes bother you enough, you will need to take out the whole package and contact the creator about the issue. Send them that screenshot also.
If this is the only issue you are having with the CC in the package, and if it doesn't bother you enough to lose the other CC in the package, you could try keeping it in and watching out for any additional issues that may be occurring or come up, plus contact the CC creator about the issue and watch for any updates from them.
Removing the cache file just helps to clear out any remnants of the issue left in cache, as cache can still affect how you are seeing the game and function.
