ChatGPT offers a permanent Free plan available to everyone with no time limit....

https://andysexpertblog.nexorafield.com/posts/how-long-does-a-chatgpt-free-trial-usually-last

ChatGPT offers a permanent Free plan available to everyone with no time limit. Occasionally, targeted users may get a free trial of the Plus plan, which sometimes requires a card and auto-renews after the trial ends