Using more vocabulary when speaking despite being able to read and understand more than I use

This is a weird thing that I feel I can't find much input on. I think I'm roughly intermediate but maybe not. I find myself able to understand a ton of stuff, even at times native speakers. But when I SPEAK it's like I'm using the SAME structures over and over again and I'm reliant on the same like 4-6 types of phrases. Im not sure if this is me beating myself up or just a limited vocabulary. Because, when I read I understand a ton, and when I listen as well. When I speak? It sounds like "Quiero+Verb" "Hay + mucho whatever" "Poder+verb" and it feels like NINETY percent of what I talk about is using Poder, querer, Hablar, cuando and decir more than anything else, and it's like..

I know all of these words beyond the things that I'm saying and I'm still using the same limited vocabulary. Why does this happen? I try to write once a week, I do input every day, I read for several hours once a week, and I (try) to speak every single day. I can have conversations that are basic, I work at a bank, so I can do most basic things in Spanish with ease, but I just feel so uneasy why the heck my brain is not using the words that it knows. I am SPEAKING people understand me, I get stuck sometimes but overall I can communicate most things, but why does it feel like I use the same words over and over! I go and read a book and it feels like there's a gajillion words I don't know, and when I speak I just kinda say the same verbs and nouns repeatedly.

How do I expand my speaking vocabulary when I already know more words!