iPhone 6 and WhatsApp

My wife has an iPhone 6 running software 12.5.6. She could previously send photos from the Photos App to WhatsApp without a problem but now it is not possible. When pressing the WhatsApp Icon in the Photos App, nothing happens. Previously pressing the icon would take you to the WhatsApp window to select where to send the Photo.

1) Size of foto or quantity of photos does not make a difference.

2) Cloud and Phone storage are at less than 50%.

3) Obviously updating IOS is not possible as it is a 6.

4) Resetting Network connections does not help.

5) Problem happens on WIFI and Cell Carrier.

6) WhatsApp is set to "Read Write" in privacy settings.

7) WhatsApp is up to date.

8) She can send from Photos App to email or Notes or SMS or Air Drop without a problem. The issue seems to be limited to WhatsApp.

Any help would be appreciated