The plugin breaks built-in is/as text objects

[dantonyuk]

Vim already has a sequence text object accessible through is/as keystroke. Unfortunately, the plugin redefined these keystrokes to textobj-sandwich.

Having it documented how to keep the built-in mapping would be great.

Something like

unomap is
unxmap is
ounmap as
xunmap as

silent! omap <unique> iq <Plug>(textobj-sandwich-query-i)
silent! xmap <unique> iq <Plug>(textobj-sandwich-query-i)
silent! omap <unique> aq <Plug>(textobj-sandwich-query-a)
silent! xmap <unique> aq <Plug>(textobj-sandwich-query-a)

[ogaken-1]

:h g:sandwich_no_default_key_mappings

The option seems good to solve your issue.