AC1200 Forgotten Password

You gave us nothing to go off.
To get a hold of support. Click on "MyNetgear" at the top.
Register an account (or login) and then the device.
From there you can start the support process. Keep in mind that its only free for the first 90 days.
There's a support site with access to manuals, firmware, install guides, etc.
Go to https://www.netgear.com/support/
Type in your model number and from there it'll take you to the above.
Its a great resource to start with.

Search - NETGEAR Communities – Forgotten Password

AC1200 is not a reliable guide to model number. Many devices come with an AC tag, but it is essentially a label that Netgear, and other brands, attach to hardware to describe wifi speeds.

Look at the label on the device for the model number.

Manuals are always a good place to start.

Visit the support pages:

Support | NETGEAR

Feed in your model number and check the documentation for your hardware.

You may have done that already. I can't tell from your message.

I mention it because Netgear gave up on supplying paper manuals and CD versions some years ago and people sometimes miss the downloads.

You can help people to help you by providing the information suggested in this forum's header:

Subject (Include model number and brief summary)
Model (Recommended - Helps the community give the best answers)
Body (Include additional detail including model version, firmware, OS and environment where relevant.)

They are there for a good reason.