I have a bass part layout where I also added the vocals for reference (to make it easier for the musician to follow the song). I made the vocals staff smaller to make it clear it’s just a reference and to emphasize what the bassist needs to play.
What instrument is used for the bass staff? For example a Double Bass is defined as Rhythm section instrument by default which is supposed to show the chord symbols.
Go to Setup Mode, open the player on the left side, (right-)click on the three dots of the instrument and select Edit Instrument Definition…
To show the chord symbols make sure that this checkbox is checked.
It depends also on this setting in the context menu of the player