diff --git a/xmpp/handlers.go b/xmpp/handlers.go
index 1d77bc4..1a47c10 100644
--- a/xmpp/handlers.go
+++ b/xmpp/handlers.go
@@ -808,6 +808,13 @@ func handleSetQueryCommand(s xmpp.Sender, iq *stanza.IQ, command *stanza.Command
 								members, err := session.GetChatMembers(toId, true, "", membersList)
 								if err == nil {
 									fieldType = stanza.FieldTypeListSingle
+									switch command.Node {
+									// allow empty form
+									case "mute", "unmute":
+										options = append(options, stanza.Option{
+											ValuesList: []string{""},
+										})
+									}
 									for _, member := range members {
 										senderId := session.GetSenderId(member.MemberId)
 										options = append(options, stanza.Option{