I can't add accounts again

To fix this I've tried signing out and signing back in. I've tried validating and repairing my file, but no joy. This is an ongoing and intermittent issue for me. I was online with a support person in December and we were able to fix this by reverting to an older backup from June or July, but I've suddenly had to take over my mother's financials because dad passed away suddenly from COVID-19 in November. I was able to add all her accounts in one session, but then I spent three weeks in December downloading and converting her various bank accounts, investment accounts, and credit card accounts. After converting all those from .csv files and categorizing the individual transactions for her tax accountant Quicken has reverted to its former state and I can't add additional accounts. I've spent too much time trying to get all the data into the program to revert back to a file from July as we did the last time. What is a better way to fix this, or do I find another program to handle my finances?

If we are able to fix the problem above, I have another problem. Quicken won't remember my preferences, i.e. I check the box that says "Don't show this again" and I see it again. I uncheck the box to show the "memo" before the "category" in my check register, but it reverts back every time I close the program. I uncheck columns I don't want to see in my check register, but there they are when I open the program next time. I'm sure there is an easy fix for all my issues, but I can't figure it out.

Any help is appreciated.