Viber problem with loading files

I changed my mobile phone from android to iPhone 12 Pro Max and I deal with a serious problem in sending and reading messages by viber application.. In fact I can not send a photo , a video or a voice message and a pdf file ! I am able only to write a message! Also while I see a receiving message  I neither be able to load a photo, video or a pdf file ! I have checked all settings about WiFi or 4g carrier but it occurs always! I checked all viber settings about photos and other files and I didn’t see difference !  I have read in internet that and other people who use iPhone have similar problem with loading or sending files ! Please help me!