I have only made $13 dollars in 3 months!

Hi,

besides what all the others written so far you also may take a look at the Guides that Adobe provide.

Adobe Stock tutorials:
https://helpx.adobe.com/stock/contributor/tutorials.html 

Create better photos:
https://helpx.adobe.com/stock/how-to/tips-stock-image-acceptance.html?set=stock--fundamentals--adobe-stock-contributor 

Before you submit, please review the submission guidelines carefully and compare your work with other Stock inventory. To be accepted, your work should be as good or better than what's already represented in your keyword category.

https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
https://helpx.adobe.com/stock/contributor/help/quality-and-technical-issues.html

https://helpx.adobe.com/stock/contributor/help/photography-illustrations.html
https://helpx.adobe.com/stock/how-to/tips-stock-image-acceptance.html
https://helpx.adobe.com/stock/contributor/help/editing-dos-and-dont.html
https://helpx.adobe.com/stock/contributor/help/vector-requirements.html

Hope that helps.

I agree with @Jill_C . Titles and keywords are your problem. Also, you need to narrow down the competition.

First of all, your titles are too long. Restrict them to a maximum of 70 characters.

The titles should contain valid search keywords which describe your image.

Too long of title which spams keywords will have a penalty effect.

The keywords in the title should be included in the top 10 list of keywords.

You should  have between 20 and 30 keywords.

Narrow down the competition.

Example 

"blurred gradient poster"  500k results

"blurred gradient wallpaper"  1m results

"vector blurred gradient poster" 200k results 

"vector blurred gradient wallpaper" 405k results

Obviously, wallpaper must be included as a keyword. However, in the title or in the top 10 keywords it is just taking up space. 

Buy the way, in my opinion, 13$ in the first three months is not bad. That is 39 sales at .33 cents a sale!

It can take a while. Earning money from stock is no quick buck! If you do a search on the net, you will see quite a few posts about earning money from stock, and the conclusion is you can make heaps of money, or, not very much at all!

Talent & creativity are rewarded when you give customers what they want.  See the link below for suggestions on how to promote yourself and diversify your portfolio to reach a wider base of customers.   

https://community.adobe.com/t5/stock-contributors-discussions/how-to-sell-stock-images/m-p/12780712#M41047

Don't give up. This won't happen in 3 months or even 6 months.  It could take 2 or more years to reach your fullest profit potential.

Your designs are nice and clean, but not particularly unique. Look at what the competition is doing and try to find something new and unique to upload. Your portfolio is not yet very large. You probably need several thousand assets before you'll start to see a substantial increase in your sales. Also look at your titles and keywords and make sure they accurately describe the asset. For instance, this one (the 2nd asset on your portfolio): 

Neo Memphis poster templates vector illustration. Abstract bold geometric banner vibrant trendy colors shapes and geometric element for posters, magazines leaflet, billboard, sales, flyers. 

Instead of "vibrant trendy colors" include the actual color names. If I need pink, purple, green or yellow, I'm probably not going to search for "vibrant, trendy". Why not include the descriptor "stars" in the title. No need to specify that the design is for "posters, magazines leaflet, billboard, sales, flyers."

Look on the Insights tab in your Dashboard to see what types of images other top sellers are achieving success with; also look at their titles and keywords to see how yours can be improved.