Strange occurrence after ending a call in WhatsApp...

When I make a call from any chat in WhatsApp, and then the call drops or I end the call, the keyboard appears even though I did not tap the "New message" box, and it has limited use. It's limited because there are no predictions, which means that I have to type each word fully, letter by letter, I have to actually tap the space bar to insert a space after a word (because there are no predictions to automatically insert a space after), and when I tap the comma, it does not automatically insert a space. It's essentially a basic keyboard at that point. For the time being, the only way to restore full functionality is to return to the main screen and then go back into a chat. It's not a big problem because I don't always want, have, or need to type immediately after ending a call, but when I do, it becomes a nuisance, but only when I am short on time or patience. Am I the only one experiencing this problem? Hopefully the developers see this, and if they do, I am using a Samsung Galaxy J7 SM-J700T1 (2015 version) with Android 6.0.1 with everything stock.