To resume the X auto responses in your first step of the sequence with step two as they are opted out, follow these steps:
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1. Go to the Prospects tab in your Sequence.
2. Select the prospects whom you want to resume.
3. Click the "Mark as Resume" button to initiate the resume process.
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Please note that if any engagement activity is tracked for the prospect during the pause, such as open, click, reply, unsubscribe, or bounce, it will be reflected in the sequence.

Also, you can use safety settings as well in Sequence Settings, which says to consider the prospect as finished if a reply is received.

Turning the toggle off will share all the emails with your prospects as per the steps you have added to the sequence. If you keep this option on, then further steps won't be shared with the prospect when the prospect replies to your sequence.