thanks, Jules, it was quite a quest) I started deactivating one by one plugins, and after reaching Loginizer Security plugin by Softacolous, I was blocked from the hosting side) so I need to ask support to whitelist me, after that I finally disabled this plugin and this was it, the form started to work as it should, and after activating security plugin back, it still working, only don’t know if is like temporarily while some scripts are active in my browser for now or it now will be working good every time.
