Facebook messenger refuses to show previews of messages, just tells me I have one

Hi, I’m not sure if this is a bug with the new iOS that you needed to download directly from a PC or Mac

but my Facebook messenger will now only alert me over the last 1-2 weeks that I have a message, not who it’s from - I’ve changed no settings & other notifications tell me but this simply says I have a notification in messenger, I’ve had previews on Lock Screen or banners turned on

this seems to be the only app now saying ‘nah uh not until you goto me’