In exploring Cardano wallets tutorial in the Starting Cardano-wallet as a REST API server section there is a mismatch in the port number.
cardano-wallet serve \
--port **1338** \
--testnet /home/user/cardano/testnet-byron-genesis.json \
--database /home/user/cardano/wallets/db \
--node-socket $CARDANO_NODE_SOCKET_PATH
&
curl --request GET \
--url http://localhost:**1337**/v2/network/information | jq
Solution: Change 1337 with 1338