Hello,
if you want to make atmospheric correction only for one granule you can change names folder others granule (eg from S2A_OPER_MSI_L1C_TL_SGS__20160104T141459_A002793_T34UCF_N02.01 TO **`**S2A_OPER_MSI_L1C_TL_SGS__20160104T141459_A002793_T34UCF_N02.01 and leave original name granule what is interesting for you.