Ibid funciton

smirnov_dd

I have inserted the ibid and subsequent functions into the code, but they don't work in the text itself when using footnotes.

Could you please tell me what is the error in the code and what needs to be changed?

https://pastebin.com/kzgPpNXm

adamsmith

Make sure your style validates, in general.
https://validator.citationstyles.org/?url=https://pastebin.com/raw/kzgPpNXm&version=1.0.2

Specifically (among other issues) you have two citation sections in the style. I'm surprised it does anything at all, but I'm guessing it's using the first one, which doesn't include the et al code.