Whatsapp have crashed

No one in this user-to-user forum has the knowledge or skill to support WhatsApp.

You can try basic troubleshooting: Force restart your phone force quit WhatsApp:

• How to force an app to close on your iPhone, iPad, or iPod touch - Apple Support

Force restart iPhone, depending on your iPhone model:

On an iPhone 8 or later and all SE generations:

• Press and quickly release VOLUME UP

     then

• Press and quickly release VOLUME DOWN

     then

• Hold the SIDE button until an Apple logo appears (15-30 seconds), ignoring "slide to power off" if it appears

The operative word here is QUICKLY; and try it a couple of times, the timing is a little tricky.

• On an iPhone 7 or iPhone 7 Plus: Press and hold both the Side and Volume Down buttons for at least 10 seconds, until you see the Apple logo.
• On an iPhone 6s and earlier, iPad, or iPod touch: Press and hold both the Home and the Top (or Side) buttons for at least 10 seconds, until you see the Apple logo.

You will need to contact WhatsApp for help with their software, this is not an Apple product.

Here is a link to their help page.

https://www.whatsapp.com/contact/?subject=messenger