@RodolfoK 

I have the same problem here. 
Whastapp does not work on mobile or desktop connected to Deco network.

It started this morning without me having changed any of the Deco settings.
Parental control is disabled.

When I bypass Deco, whatsapp works normally.

Deco M5 Firmware version 1.5.3. 20210203 Rel. 68223..

@EduLad that's exactly what is hal

@TP-Link 

All the devices (Android, IOS and Windows) were with the same issue.

I have a Tapo cam that wasn´t working in Deco network too, showing off status.

I switch to access point mode and everuthing is working fine.

What kind of configuration could cause it? Parental Control and QoS is off.

Thanks for your help.

@EduLad neither my laptop. 
I reseted all my network and still wasn't successful. But a left home for work and when I came back at night everything was normal again. 
It fixed the same way it stopped  working without a reason 

  @TP-Link 

Hi, i have an issue with my deco M5, where whatsapp would repeatedly keeps “reconnecting”, i couldn't send or receive any messages or calls. I could browse the internet just fine but whatsapp is so glitchy. 
Things i tried:
1: Turn off Beam forming and fast roaming(no effect)
2: change to access Point Mode(in this mode whatsapp would connect when i open the app, but i couldn’t  receive incoming notification when the app is closed)
3: Wireless Router with antivirus and safety features turned off(the same whatsapp would have a very hard time to connect)
4: Tried plugging in my old router and the whatsapp connection is stable(so i can conclude its not my ISP fault)

  @RodolfoK Seninle aynı sorunu yaşadım ama instazoomhd  bunu yapabilen geliştiriciler sayesinde çözülmüş gibi görünüyor