Welcome to the community forum!
Do yo use a custom keyboard? Could you provide screenshots so that we can understand your problem better?
The icon for voice messages in these apps is separate from the keyboard, does this mean that the keyboard doesn’t even show up?
Was it the update to android 10? In this case you’re not the only one:
If not, which update was it? Are you up-to-date (I suppose you are if you did an update recently)?