Trouble canceling my free trial before I get charged

I don't need Capture One so I'd like to make sure that once my free trial period is over I won't be charged. Like most other free trial programs, I looked to cancel my free trial before I get charged. 

I'm having trouble accessing my account management so I can cancel. I go to manage licenses > Manage subscription - I'm then asked to enter my email. I enter it. The website then says "An email was sent with instructions for accessing your account". 

The problem is I have yet to receive any emails about managing my account or my trial subscription. Can someone please help me figure out how I can make sure I won't be charged before a possible subscription begins. 

Thank you!