String requestNick = getFieldValue(fields, "muc#roomnick");
Occupant requestor = room.findOccupantByNick(requestNick);
requestor.setRole(Role.Participant);
// notify remaining users that user got role updated
MucUserItem presenceItem = new MucUserItem(requestor.getAffiliation(), requestor.getRole());
for (Occupant occupant : room.getOccupants()) {
Stanza presenceToRemaining = MUCStanzaBuilder.createPresenceStanza(requestor.getJidInRoom(), occupant.getJid(),
null, NamespaceURIs.XEP0045_MUC_USER, presenceItem);
relayStanza(occupant.getJid(), presenceToRemaining, serverRuntimeContext);