Unfortunately, the information that you have provided indicates that you will need to reset the Time Capsule back to factory default settings and then set it up again.
With the Time Capsule (TC) powered on, hold in the reset button on the back of the TC for 7-8 seconds and release. Allow a full minute for the TC to restart back to factory default settings with a slow, blinking amber light status.
Check again to make sure that the Ethernet cable connects from a LAN <--> port on the router to the WAN "O" port on the Time Capsule
Click the WiFi icon at the top of the Mac's screen and look for a listing of New AirPort Base Station. Just below that, click on Time Capsule. The illustration below shows an AirPort Extreme, but you will see Time Capsule on your screen.

When you click on Time Capsule, that will get the setup wizard running. It will take a minute to analyze the network and then present a screen that looks similar to this, except you will see a picture of the Time Capsule.

Network Name.......Type in a name for the TC wireless. Later, we will turn off the wireless on the TC if you don't want to use it.
Base Station Name......Type in the same name that you used before with the Time Capsule, or you can change to a new name
Password......Type in a password for the wireless and the Time Capsule device. You can use the same password that you used before if you wish, or type in a new password
Verify.....Type in the password again to confirm
Click Next
The setup wizard will configure everything for you. When you see the message of setup complete, click Done. You should have a green light on the Time Capsule now. Post back on your progress.