As key social media websites suffer outages every now and then, it was the turn of AI conversational service ChatGPT to go down for most of the users, including paid subscribers, and their chat history also went unavailable for several hours.

ChatGPT, a product of Microsoft-owned OpenAI, suffered a day-long outage as users were unable to process writing, coding as well as taking its assistance for several topics.

The issue affected ChatGPT on the web, and also impacted paid subscribers of ChatGPT Plus which is now available in India.

OpenAI said in an update late on Monday that it was gradually rolling out a fix that "users will receive as capacity allows".

According to website-monitoring service Downdetector, a much larger outage began and wasn't fully restored nearly 12 hours later.

Despite service being back online, there's some issues still occurring.

"Service is restored, but conversation history is still not available," said OpenAI.

"We have a root cause for the loss of conversation history and are actively working to restore it now," it added.

The latest update by OpenAI on Tuesday said: "We've fully restored ChatGPT service to all users. We're continuing to work to restore past conversation history to users."

An affected user posted on Twitter: "ChatGPT being down in 2023 is like the Wi-Fi being down in 2013."

OpenAI last week announced that ChatGPT Plus, the subscription service to access its text-generating AI, is now available in India.

GPT-4, the refined AI model released by OpenAI, is included in ChatGPT Plus.

Compared to GPT-3.5, the new AI model is more reliable, creative and capable of handling complex instructions.

Moreover, customers on the paid tier gain early access to new features including GPT-4.

ChatGPT Plus, which was released in the US in February after a brief preview period, costs $20 per month.