You need to just listen more to native speech. With no stats on LingQ I can’t tell how many hours of listening you’ve actually done…but it will take hundreds of hours before you will be able to understand two natives talking to each other.
I would suggest listening more in general, podcasts, audiobooks, youtube, movies. Ideally with a transcript to review and/or follow along. If you are on LingQ you can import these if you have them. Or if on Netflix or Youtube you could use Language Reactor program to help.
I’d further suggest the Easy Spanish youtube channel. If you’re not familiar, most of the videos take the form of the Easy Spanish team going out onto the street and asking natives questions on a particular topic. You’ll get authentic native speech complete with the mumbling, abbreviating, pauses, restarts, etc. Also, the subtitles, both Spanish and English, are burned in, so you can follow along. If you become a patreon supporter you can get the transcripts as a separate file. (Importing into LingQ from youtube will just give the autogenerated subtitles (unless something has changed for this channel) which are ok, but not ideal).
Listening is just simply difficult. You are used to reading at your own slow pace (in comparison). You don’t have a chance to catch up, unless you have a pause button or can slow down the speed of the sound. Reading and listening at the same time you might find helpful. This will help keep you at a good pace and force you to try and comprehend quicker. It will also allow you to see the words with the sounds and form those associations. You can speed up the sound as you get better. You can also review the text on its own to look up words and phrases you don’t know.
Of course, you also need to read more. The more words you know the better. Plus you also need to speed up your comprehension of words you already know and reading more and more will help with that, either with or without listening.