@ Ren I totally agree with Tiana - you can get good rates without a site like Fiverr.
Your work is good enough. I also agree that it can make you look less than what you are by being on there.

Many, including me, got started doing comms right here on the Map Request forums.
If you have any specific questions about anything in the process of getting clients or further, feel free to ask. Here, or in a dm.
I know myself, and most of the rest here doing work commercially would be happy to answer.
We have all been there before.

One quick suggestion - I noticed you seem to only be on IG.
Start an artstation account. That will help.
Having a website does a lot too.
Having a focused portfolio space helps to get more commercial work, which pays better than personal work for people's personal games.
[I like doing some for people's personal games, but they don't pay enough to pay the bills most times.]
I've seen a lot of comms coming from my brief time on twitter, and there is a good supportive community of mapmakers on twitter.
Thomas is your best ally and advocate there, trust me.