A base station transmits configuration parameters of a plurality of cells to a wireless device. The plurality of cells are grouped into timing groups and control channel groups. A primary control channel group comprises a primary cell with a primary control channel received from the wireless device. A secondary control channel group comprises a control secondary cell with a secondary control channel received from the wireless device. The control secondary cell is in a first timing group of the timing group. In response to expiration of a time alignment timer of the first timing group: transmission of downlink shared channel transport blocks to the wireless device via a first secondary cell in the secondary control channel group is stopped and transmission of downlink multicast channel transport blocks to the wireless device continue via the first secondary cell. The first secondary cell is different from the control secondary cell.