Reinstall El Capitan

My Mac slowed way down until it finally would not boot at all. Now it sends me directly to the disk utility.

After many reboots and running first aid multiple times, I finally erased my disk.

Now I am trying to reinstall El Capitan.

After entering my Apple ID and Password, it pauses, and gives me the following error message -

"This item is temporarily unavailable"

"Try again later"

After more than a dozen tries over two days, it seems unlikely that it is "temporarily unavailable", but rather something else.

Does anyone have any ideas on this?