Schedule C and car depreciation

On Schedule C, under Expenses:
Car depreciation: this one, EVERY YEAR OF MY LIFE, and I've been self employed forever, confuses me. I've looked back through my last six (2015-20) years of taxes and I see the form 4562 sometimes yes and sometimes no. (I did have a different - new-used - vehicle starting in tax year 2018). Previous vehicle, a 4562 filed: 2015 and '16, yes; 2017, no. Current vehicle acquired 2018 (used): no 4562 in 2018 (2018 was NOT me doing turbotax); 2019, yes, 2020, no.
Why worried: Last year, for 2020 taxes, line 9 has a very low amount, this year it's WAY higher. What did I do?? Did I switch between standard mileage deduction and actual expenses?? Since it's now 2022, I've had the car 4 years, and only one more year to depreciate anyway (yes??) PLUS I have barely driven it for use cos of Covid other than errands for last two years. What is the easiest thing to do? At this point I don't care if I get more or less refund. Just want to finish fed and get to state taxes! Someone please help me, I hope. 😫