Geometric correction of Sentinel-1 data using PolSARpro

Hello Mr Braun and Polsarpro users,
Good morning, I have a problem with geocoding on Polsarpro.
When I processed the Sentinel1A SLC data, I followed the relevant steps to generate the C2 matrix (i.e., input S1 SLC—>extract data, multilooking 1*5, C2—>get C2 matrix).
However, a error happended when geocoding the C2 matrix, the running time was too long (exceed one day). I tried to import the dem data from outside to re-run, but an error was reported at this time. The error is as follows.
image

How to solve this problem, and run the geocoding successfully?
Looking forward to your reply. Great thanks!