The three addresses
The block above is the complete current set. All three addresses reach the same backend: one account, one balance, one order history. There is no main address and no fallback, they are interchangeable.
How to read an onion address
Each address is 56 characters plus the .onion suffix. The 56 characters are base32: lowercase a through z and the digits 2 through 7. By convention they are written lowercase. The string encodes the service's public key, a routing key, and a checksum. It is not a domain name in the DNS sense. There is no registrar and no lookup table, the string itself carries the routing information.
Why one wrong character matters
A different string is a different service. Nothing stops a scammer from registering an address that looks close, and the prefix "awazon" is plain enough that it is cheap to repeat. So the check is simple: copy the address from the block above and compare the whole string against what is in your browser bar. At minimum, compare the first eight and the last eight characters. If anything differs, stop. The full procedure is in how to verify an onion address.
When an address you found does not match
The set rotates. When the operator changes it, the announcement is a PGP-signed post on the Dread forum, and that is the only official channel. Other directories and forum posts usually keep the old set for a while. If an address you found elsewhere does not match the block above, it is either stale or a clone. Do not log in with a password until you have checked it. If you are stuck on this, troubleshooting covers the usual cases.
Pasting hygiene
Use the full string, including .onion. No trailing spaces, no line breaks inside the address, all lowercase. If your browser complains that the hostname is invalid, you probably copied something extra. Delete it and copy again from the block above. The first-visit guide in getting started walks through this in order.