Do you have a capacitor between GND and 3.3v on the ESP8266-01? It's been a while since I used an 01 but I the thing did keep resetting without the capacitor.
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I'm going to say power is unstable/insufficient.
Do you have a capacitor between GND and 3.3v on the ESP8266-01? It's been a while since I used an
01
but I the thing did keep resetting without the capacitor.