Instagram cache DELETION

Hello,

Instagram DM notifications stopped working for me on all of my accounts on my iPhone 13 Pro.

I did factory reset, but recovered my iCloud backup - so, after one hour that I lost nothing happened and I still do not get my notifications of DMs, which I need because it is my main way of communication with people and clients.

Instagram settings are okay, everything is allowed. All other notifications work, only DMs not.

Whenever I uninstall app Instagram (and totally "clear" data), after installing it back I am logged in on all of my accounts... so cache was not cleared...

HOW CAN I PLEASE CLEAR APP CACHE FOR REAL TO GET MY DMs NOTIFICATIONS BACK?

Thank you, thank you very much!