emacs does not give me to add quotes around my word in Scheme-Mode

[znavko]

Hello!
I use emacs 26.2 to edit my guix config.scm. It is awesome, but rests unobvious 
things I cannot get.
When I have word that I want to place in quotes, emacs does not give me to add 
quote before the word and after -- instead of this emacs closes quotes 
automatically and does not give me to delete only one quote. Like this:

(shell (file-append dash /bin/dash/)) -- I want to place /bin/dash into quotes
(shell (file-append dash "" /bin/dash/)) -- here I've just typed one quote, but 
emacs autofinished it.
(shell (file-append dash /bin/dash/)) -- here I've tried to delete one quote, 
but emacs has deleted both!
(shell (file-append dash "")) -- so I can only delete my word and add quotes
(shell (file-append dash "/bin/dash/")) -- and only then type it again.

It is so bad inconvenient, extraordinary for editor. Please, how to deal with 
it?