ChatGPT offers a permanent Free plan with basic features available to all...

https://smoothdecorator.com/how-do-i-check-if-im-about-to-be-charged-for-chatgpt-plus-on-android/

ChatGPT offers a permanent Free plan with basic features available to all users. Occasionally, targeted promotions provide a trial of the Plus plan, which may require a payment card and auto-renews after the trial ends