smart controller update

My Smart Controller flashed up as needing a firmware update on. However, insufficient space for an update always shows. I've used 9.17GB out of 11.24GB. Apps - including Litchi = 1.34gb Other = 7.83gb Listed under "OTHERS" are DCIM - 1 folder DJI - 6 dji_logs - 1 file and 6 folders DOWNLOAD...