You will see in your Terms and Conditions which entity you have registered with - Trading 212 UK Ltd. or Trading 212 Markets Ltd.
If you have an Invest/ISA, you need to check your Share Dealing Service Terms of Business. You can access the document by going to your Menu and pressing Share Dealing Service:
If you have a CFD account, you need to check your Client Agreement. You can access the document by going to your Menu and pressing Client Agreement: