In wireless communications for multi-users, a station may generate a first frame and transmit the first frame to an access point. The first frame may include media access control protocol data units (MPDUs). Each MPDU is associated with a traffic identifier (TID). In one aspect, a TID of one of the MPDUs is different from a TID of another one of the MPDUs. In response to receiving the first frame, the access point may generate a second frame based on the first frame. The second frame may include an indication that all of the MPDUs having TIDs are received. The access point may transmit the second frame to the station. Other methods, apparatus, and computer-readable media are also disclosed.