Height forest

I want to extract height forest with RVOG model. my data is ALOS-2 and dual-polarization. I wanted to extract coherency matrix but I understood that I need to full polarization data. how can i work with dual polarization data?I can extract (Sxx, Sxy) for Master and Slave image but next step, when I wanted to enter these (S) for master and slave I saw this error: