After Mosaicing,raster size change,thanks

i have 2 S2B-L1C img,i have processed via Sen2cor and resampled 10m via S2 resampling Processor,but after Mosaicing, raster size changed???

Mosaicing merges adjacent products together so it is logical that the extent (width and height) of the raster will increase. Or did I misunderstand your point?

oh,i know.thanks for your answer