Circuit for the automatic reset of LilyGo SIM800L IP5306

[Tirititelu]

Hello everyone. I am trying to set up a circuit with a LilyGO SIM800L IP5306 version and another microcontroller that every so often resets the LilyGO through the "EN" pin. The circuit in question, consists of the LilyGO, a Lolin D1 mini Pro (although it could be any other that had a battery connector) and a battery charger TP4056. All this powered by a 3.7V battery that is recharged by solar energy. To control the on and off of the Lolin I have used a BJT transistor, specifically the BC547B connecting to the "base" pin the positive of the solar panel, so that if a night or a day without sun the 3.7V battery is discharged and the LilyGo turns off, when it is day again (there is sun) and the battery has recovered enough voltage, the Lolin resets the LilyGo to work again. The scheme is as follows:

The problem I am having is that I do not know how to go directly from the cut-off zone to saturation of the transistor (and vice versa) without passing through the active zone, since when passing through the active zone (when it is dawn for example) although at the end the plate reaches 6V the Lolin does not start until I disconnect and reconnect the solar plate (or cover it completely and then uncover it), ie, go from 0V to 5V in a single moment and not prograsivamente.

I hope I have explained myself well. Thank you very much.