I want to cancel my Adobe Stock Plan (monthly) but I don't have the option to change plan, when I go on my account page...
Sorry to hear that.
I have checked your account and noticed that you had an Adobe Stock 10 images a month(one-year) plan which has already been cancelled.
Also, there is another Stock subscription 3 images a month (month- month) plan under the Adobe ID shared in the forums which is suspended due to payment issues.
If you are trying to cancel this subscription and switch to another plan, please contact our support team Support FAQ: How can I contact Adobe for support? for further assistance.
If you are unable to reach our support team through the above- mentioned link, please see Contact Support FAQ: Unable to reach support through the "Contact US" link
Feel free to update this thread in case of any additional questions.