Seagate external HD won't connect to MacBook Air

1. This is a user to user forum. You are not addressing Apple here.
2. Seagate external drives are not Apple products, as such there's no way for Apple to have an update to patch a device they have nothing to do with.
3. Why can't you use your external drive exactly? How is the drive formatted?
4. Did you recently update your macOS version?
5. Were you using some type of Seagate software to access the drive?
6. Have you contacted Seagate support directly for help with their products? https://www.seagate.com/support/

It's unlikely an update from Apple will make the drive work.

Since you just recently had an update, it's entirely possible the update messed up the Seagate software used to access your drive.

Apple will not offer a patch specifically for your seagate drive. They have no way of knowing what if anything may have gone wrong with the drive or its own software. Only Seagate can know that.

Let's start with some simple steps.

Does the drive show up in Finder?

If so, what happens when you try to open it?

If it doesn't, use spotlight search from the menu bar at the top, and look for an App called Disk Utility. It will list all drives connected to your Mac.

Open it, and see if the Seagate drive appears there. If it does, tell us how it is formatted please. It should tell you this below the name of the drive when you select it.