I’m grasping at straws here but is that backquote in “I`m” a valid character for Pushover?
You say the log shows no error message. Does it contain an INFO message indicating something was, in fact, sent?
If you login to your Pushover account, does it have a record of messages sent (or at least a running count) so you can confirm it received the message but (for whatever reason) refused to forward it?
Possibly because there’s nothing logged for that service at a debug level for sending a one off notification. I don’t know, I don’t play with the logger settings.
And was one more problem, my boolean somehow is turned off. Maybe you can help me with this too? Why boolean state is off, if I turned it on at frontend. After restrart hass it can be off again?
This component will automatically restore the state it had prior to Home Assistant stopping as long as your entity does not have a set value for initial . To disable this feature, set a valid value for initial .
initial
(boolean)(Optional)Initial value when Home Assistant starts.