My wi fi is saying weak security and didn’t use to state this. What should I do ?

Contact your internet provider and ask them to re set up your modem/router for WPA/WPA2 personal(AES) because probably you got WEP that is very bad security because anybody can guess your wifi password

Here are the ➡️ Recommended settings for Wi-Fi routers and access points - Apple Support

WEP, WPA, and WPA2 TKIP are considered less secure or insecure.

WPA2 AES, WPA2/WPA3 transitional, and WPA3 are considered more secure

Post the specific vendor and specific model of Wi-Fi router. That’ll usually allow us to find the vendor description of how to update this—there’s usually a discussion at the carrier’s,website, as there are a lot of Apple devices in use—assuming the Wi-Fi router can be updated to at least WPA2 AES.

While you’re connected to the Wi-Fi router, check for firmware updates, and apply any available.

Or you ignore this, as nothing here has changed, except you now know your Wi-Fi security is weak.

Basically, your Wi-FI router needs to use either WPA2 or WPA3 encryption.

If it does not, you will see the message about poor security.

In reality, it's up to you, it doesn't really "hurt" anything other than to let you know that WEP and WPA encryption are not secure, you need to upgrade to WPA2 or WPA3.

Doing so may be as easy as enabling an option on your router, or you may need to purchase or rent a new one.

Edit: Ugh. And I see I’ve duplicated Dogcow-Moof’s answer. Ah, well…

Looks like it might be possible to get to WPA2 AES with that, based on the images here:

https://www.att.com/support/article/u-verse-high-speed-internet/KM1049981/

But it’s unclear if that device can shut off WPA2 TKIP.

It’s a pretty old device, but again, nothing here has changed. Other than that you know know the Wi-Fi connections are considered weak security, that is.

Inferring from the reported response from AT&T Support, I’d tend to guess that this device can’t be updated to WPA2 AES, and they probably don’t want to replace it.

It's unclear whether the Pace 5031NV supports WPA2-only mode, so you may not be able to change settings to get rid of the message as it will be triggered by the recommended "WPA and WPA2" setting.

If you can select WPA2 only, that should solve the problem.

https://www.att.com/support/article/u-verse-high-speed-internet/KM1049981/

Really, it's not that big a deal if you don't want to experiment further.

Call AT&T back and ask for tier two support for your router. Do you have DSL, Uverse or Fiber?

Recommended settings for Wi-Fi routers and access points - Apple Support