Issue with BTCTestnet

[AlessandroSechi]

Following the example in readme,

var (
	mnemonic = "range sheriff try enroll deer over ten level bring display stamp recycle"
   )

   func main() {
	master, err := hdwallet.NewKey(
		hdwallet.Mnemonic(mnemonic),
	)
	if err != nil {
		panic(err)
	}
	wallet, _ := master.GetWallet(hdwallet.CoinType(hdwallet.BTCTestnet), hdwallet.AddressIndex(0))
	address, _ := wallet.GetAddress()
	addressP2WPKH, _ := wallet.GetKey().AddressP2WPKH()
	addressP2WPKHInP2SH, _ := wallet.GetKey().AddressP2WPKHInP2SH()
	fmt.Println("BTC: ", address, addressP2WPKH, addressP2WPKHInP2SH)
   }

outputs BTC: mz5otQWaaPmWEydGw9gjfaHxSKhHX6Fgj5 tb1qew503ut4u9xpe6gu0md2ymfa4nzx5s4uw7zm4v 2MzibkYjFqqAu9TYtK3SraqQTo226vrLD6L

but it seems wrong, as creating a BTCTestnet transaction (TX ID: 0ae7c88251d0a8bed462141fc1d4605370367069ccb27b77b970c51e1103f68d) doesn't show up in wallet generated with the previous mnemonic seed