Strange behaviour in vim with parentheses

[Big-bros]

Hi,
I'm learning quacken (owl) + ergol.
In vim (and only there), SYM+S / SYM+E don't produce ( ). I have to do them with *L / *R.
As it seems to work everywhere else, i guess this combination is conflicting with one of my vim shortcuts but is this possible ?
and if yes which one (well, if this hypothesis is right, i'll search by myself) ?
Which AZERTY / ANSI combination is SYM equivalent ? CTRL+ALT ? CTRL + MAJ ? ALT + MAJ ?

[Big-bros]

I deactivated all my mappings but the problem is still there.
In fact, i discovered accidentally i can type ( and ) with SYM but i have to roll ES for ( and SE for ). And only in Neovim. Everywhere else SIM+S = ( and SYM + E=)
Really strange.