Hello, I too have seen this error.
Running the latest update on Switch. Day 25 of Winter, Year 4, giving Evelyn a Tulip for Winter Festival. She says her lines, then the screen fades like it's going to go to where I get my gift, then the app closes because of a problem.
Reran the day, mostly the same, gave her a Tulip again, same issue.
Just tried again with Chocolate Cake. Same error: The software was closed because an error occurred.
I'm a developer too and know these types of bugs can be un-fun. :)
PS. I spotted this in early March, 2021.