I wish I'd had known the issue earlier,
You can thank our wonderful education system for that. I can recall my home economics class back in my high school years where we learned how to budget, balance a checkbook, do taxes, house buying, car buying, grocery shopping, dealing with credit and many other things that required financial planning and running a household. These are essential life skills that should be required for HS graduation. Ever since president Carter enacted the U.S. Dept of Education, back in 1979 things have go downhill on that front every single year since then. The subjects of home economics and social studies was no longer taught in my school district starting sometime in the late 80's and early 90's. A vast majority of today's young adults were not taught any life skills in grade school, and for many not even in college. It's dismal. I find it appalling when a college student complains because only their W-2 box 2 taxes were refunded, and not their box 4 SS taxes or box 6 Medicare taxes were refunded. They have no knowledge of how the tax system works at all. I've even seen posts here where folks expect to get "all" of their taxes back, no matter how much they made during the tax year. It's not that they're stupid. It's that they've never been educated on how our economic and tax system works. For that, I blame my generation, one hundred percent.
Should I seek another CPA to help me correct this
To correct things the right way, that would actually be the best way to go, and the 3115 would definitely be necessary. But I would suggest you let them know you do not want to e-file, and will instead sign and mail it yourself. That way, you can review it first and ask questions to educate yourself and increase your knowledge on the subject.
When you say "correct" do you mean the amount it should have been
No. I mean you will enter the actual incorrect amount of the total prior year's depreciation that was actually taken. The program will then compensate for that and decrease the amount of depreciation that will be taken for the 2020 tax year. That will get things "back on track" starting with the 2021 tax return you will complete next year. But if you seek professional help (which is best) so that the 3115 is completed correctly, then this action would be a moot point.
