Quick reply for 3rd party apps stops working after 9.3.2.

I'm using an iPhone 6 Plus. Quick reply for 3rd party apps, i.e. Whatsapp, Viber etc. stopped working after updating to IOS 9.3.2. I don't have any 3rd party keyboards installed & I'm using the latest version of Whatsapp. Quick reply works fine with iMessage.

I restored the phone & quick reply worked briefly but has stopped working again. I've contacted Whatsapp but their reply was that this is an issue with IOS.

Quick reply on my partner's 6 Plus running IOS 9.3.2 works fine with Whatsapp & my settings are the same as hers.