plantuml encode is not right

[f4haofeng]

func TestPlantUMLBase64(t *testing.T) {
	var str = `@startuml
Bob -> Alice : hello
@enduml`

	encoded, _ := plantuml.DeflateAndEncode(str) //https://github.com/orlade/plantuml-encode
	fmt.Println(encoded)
}

print:
UDfoA2v9B2efpStXSifFKj2rKt3CoKnELR1Io4ZDoSddSaZDIodDpG44003___W93C00

https://www.plantuml.com/plantuml/png/UDfoA2v9B2efpStXSifFKj2rKt3CoKnELR1Io4ZDoSddSaZDIodDpG44003___W93C00
that is not right