Fritz 15 doesn't play play a brutally strong game at that setting so I'm not sure what to tell you. It probably plays stronger than 900 but it's still pretty weak.
If you reset your rating, you can tell the program you're a beginner and Fritz will lower its stated rating to 700.
I recently bought a copy of Fritz15. Its "friendly mode" is not friendly at all, but plainly hostile. I am not an experienced club player, but I am not a beginner either. Yet, when I play the friendly mode of Fritz 15, I am systematically defeated 90% of the time, which is very frustrating. Fritz seems to play at brutal strength even at 900 ELO, and I can't find a way to lower the ELO further. Is it me, or I am missing something in the software setting?