After the recent software update my ROG 8pro front camera has stopped working there is no option to switch between front and rear camera as there is no option and also it doesn't work on WhatsApp and Instagram but works on Snapchat
Try clearing the cache of WhatsApp and Instagram, and then check it out, it happened to me as well but it was with the remini app and then i clear the cache and and reinstall it. For me that worked smoothly.
As @Shakira mentioned, it could be a cache issue, you can do this by longpressing the app icon > App info > Storage and cache > Clear Storage and Clear cache
