ChatGPT offers a permanent Free plan anyone can use without a time limit....

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

ChatGPT offers a permanent Free plan anyone can use without a time limit. Occasionally, targeted users get Plus plan free trials, which may require a payment method and auto-renew after the trial ends