The comment section is not great for replying with images, so here is the explanation with a few screenshots:
I had a quick look at my trial account and the documentation that SAP has is a bit outdated (i.e. https://developers.sap.com/tutorials/mendix-onboarding.html - Neo doesn't exist anymore and these screenshots are not accurate either).
Step 1: Go to https://cockpit.hanatrial.ondemand.com/cockpit/#/home/trial and click "enter your trial account".
Step 2: Under the "New Subaccount" button, click on the trial subaccount.
Step 3: In the middle of the page, there is an area called spaces.
See whether there is anything in there that you do not need or use anymore. This is also where your Mendix services will be "Under Service Instances".
Delete everything you don’t need here (including your existing Mendix application). You can then recreate the environment and it will hopefully provide you with what you are after.
Note that when you select a database, that you don’t select postgres as it is no longer supported. Choose HANAtrial or one of the AWS options.