When you sign up for a trial, Adobe requires payment information from you so that it can start charging when the trial rolls over into a subscription if you did not cancel the trial before it ends.
If there is an issue with the payment information, it won't let you cancel the trial.
If the information in this link doesn't work, your only option is to talk to customer support.
This is a public forum, not Adobe support. Users, including the ACPs and MVPs, can't provide support for account, subscription, billing, download, or product activation issues. Support for those issues requires an Adobe employee.
Click the following to contact Adobe customer support staff for help:
You must be signed in with your Adobe ID and allow cookies in your web browser for this to work.
This is the link to the US website. If you are not in the US, the site should redirect to the page appropriate to the region associated with your ID.
Click the chat icon at the bottom right of the page to open a chat session. Typing AGENT into the chat window should connect you directly to a CSR rather than the AI.
If the CSR refers you to the forums, insist on speaking with a supervisor and keep moving up the chain until you get someone who knows what they are talking about.
You can also search for Adobe customer support using your favorite search engine. This will normally provide you with a regionally appropriate phone number that you can use.
Be aware that because of the pandemic, wait times are far longer than usual due to reduced staff and higher demand. Please be patient with the people to whom you speak. Like you, they are feeling a great deal of stress. A little patience and understanding will go a long way to helping you in your particular situation.