Time capsule

Thanks for the additional information.

Please power off the Time Capsule by pulling the power cord from the back of the device or pulling the plug from the wall AC socket, whichever is easier for you.

Restart your Mac

Power the Time Capsule back up again and let it run for a minute

Click on the Time Machine "clock" icon at the top of the Mac's sreen

Click on Back Up Now

Keep an eye on the process and post back with any messages that appear on your Mac's screen. Because you have updated the operating system on your Mac and Apple has made major changes with Time Machine in Monterey, it may take a long time for the backup to begin and complete

You can watch the progress of the backup attempt by clicking on the Time Machine "clock" icon on your Mac and then clicking on Open Time Machine Preferences. You may see "Preparing" for a long time before the actual backup begins......if it can run.

Post back on your results, please.

In a number of cases where Time Machine has issues after an update to Monterey, the only thing that seems to help is erasing the Time Capsule hard drive and then starting over again with a new backup of the Mac, so you might keep that possibility in mind.

Finally, even if we can get things going again, it is time, or past time actually, to start thinking about a replacement for the Time Capsule. You would not want to keep data on the Time Capsule that you cannot afford to lose, unless you are also backing up to another hard drive.

I have had a one terabyte Apple Time machine for about 5 years

Apple discontinued the 1TB version of the Time Capsule in October of 2009, so your Time Capsule is actually older than you might think, unless it was not used for a number of years before you installed it on your network.

The power supply and hard drive on the Time Capsule have an average useful life of 6-7 years, so that might be a possible factor here.

I can't get my time capsule to work

Sorry, we are not sure what "work" might mean here.

Does the Time Capsule not power up at all?

If the Time Capsule powers up, is the indicator light on the Time Capsule front panel green, blinking amber, or solid amber?

Have you seen any error messages displayed on your Mac's screen when you try to run a backup? If yes, please post the exact text of the message.

Please remember that we cannot see your network devices or know what you might be thinking, so things that are obvious to you are totally unknown to us. Basically, we will only know as much about your issue as you can tell us. Thanks for providing additional details.