Terrain correction ALOs palsar L1.1

I am aware it exist but I have to confess I didn’t check if the coverage for my area is included. The signals I’m searching for are very small and get easily diluted in speckle filtering. My final goal is to play with that but first oc I had to see the standart post preprocessing result, where this problem occured.
Thank you very much for notifying. I will keep in mind for future purposes