Last month, Elon Musk-led microblogging platform Twitter had said its two-factor authentication (2FA) security feature via SMS would go behind a paywall and will not be available for free users.

The company said the step was taken it believed the feature was being abused by “bad actors”.

Starting Monday, the security feature will only be available for Twitter Blue subscribers.

The security feature requires a user to use a second authentication method in addition to a password to access their accounts.

Accounts that currently have SMS 2FA enabled will be automatically disabled.

Twitter in a blog post said it encourages non-Twitter Blue subscribers to use an “authentication app or security key method.”

The move comes as Musk looks for ways to monetise the platform. Twitter last month said it has rolled out its subscription service, Twitter Blue, to users in India, Brazil and Indonesia.Twitter Blue gives users access to additional features such as the blue check mark and the ability to edit a tweet, post longer videos, etc.

Subscribers will also get priority access to Twitter’s new features.

In India, the service is available for a monthly fee of Rs 650 on the web and Rs 900 on mobile devices.

The microblogging platform also offers a discounted annual plan of Rs 6,800 per year, which comes to Rs 566.67 per month.

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