I love this point . yesterday i am facing the same issue for my website. recently some of the told me to change to website title as well as description. I changed it and check it on google search
Its shows the older one. then i submit my home page url and fetch it on google webmaster . afterwards its works very fine. its shows the coreect description and title on google search.
But still my problem didnt solved on facebook share . i am using yoast seo plugin . i clear all the data on facebook in yoast plugin and try the same . but still same error.
Later only i found out debug tool on facebook.
I check my links on it . its shows the old one. i click on scrap again . then it comes with new update title and description.
Note : If anyone update any changes on your post title and description. then share not showing corrctly on facebook means, first check the debug tool using your link. it will shows the full result about that link. Its the cache problem main faced on facebook.
Thank you .