Hello @Lvgmannhi, welcome to our Community, I'm happy to help you with this! When I search on your email address, I come across the number ending in ***6287. In doing so, I see that you are still in contract through 18-9-2025. If you want to cancel the contract, you have to buy it off. You then pay 50% of the monthly costs for the remaining months and the device credit you still have open (if you have one). Now I see that you have a Sim Only subscription. The earliest I can stop this for you is 30-09-24 due to one month's notice. Would you like that? If you have the subscription stopped on this date, it will cost you € 83,91. 

Feel free to let me know if you agree to this. I will just have to do an additional verification with you to make sure you are the right person. Are you still in possession of the SIM card? Then I will send a verification code by SMS to the number and otherwise by email!