This is an issue with the Jetpack Compose in Amethyst and stock AOSP keyboard that must be built in for broader system requirements. GrapheneOS keyboard IS the AOSP keyboard and unfortunately due to Google prioritising their GBoard fork of it for development AOSP kryboard gets left behind.

You can use GBoard with network revoked, Florisboard for a FOSS option or any other keyboard (Anysoft, SimpleMobileTools et al) too, to resolve the issue.