How can I delete unwanted keys in spacemacs org-cite/citar?

I am trying to use org-cite and citar-embark to manage my citations. I am okay with selecting (multiple) keys and editing citation styles with C-c C-x @ and embark-act. But the problem is, when I choose citation (keys) in the minibuffer, I couldn't delete keys I didn't want.

For example:

Keys (empty imput exits): Citation1;Citation2;

If I don't want Citation2 and hit backspace, I quitted the whole minibuffer, rather than just deleting Citation2. I tried couple ways but nothing worked. I know org-ref can do what I wanted but I have to use citar-embark to keep the same citing style with my colleague. Can someone have any suggestion for this?

BTW, I use ivy. Command-log shown that when I hit backspace within the minibuffer, the action was ivy-backward-delete-char and then I quitted the minibuffer, if this info helps.

From what I know, this issue is unrelated to Spacemacs. It seems that ivy does not support completing-read-multiple well?

I am using vertico and consult which work as the described functionality.

Possible suggestions:

1. Use vertico and consult.
2. (setq citar-select-multiple nil).
3. Use citar-capf completion instead of inserting citation with org-cite-insert.