TIME CAPSULE BACK UPS ARE GONE

My airport time capsule back-ups are gone, except for the recent month November.

On finder I click Airport Time capsule/data/sparsebundle, it gives me a pop-up box indicating;

iMac.spars Resource temporarily unavailable

I checked my wireless network, seems OK.

I have resarted the computer

Nothing changes.

How can I access my back-ups?

Thank you for your support.