ro85ac

Depends on the type of the sensor you have bought. There are 2 types: one with DHT12 and the other is with BME280. You cannot have both. They measure the...

@rto54 depends on what type of HiGrow board you have: the one with DHT12 or BME sensor? To which server you want to make the MQTT connection ?

@thecolorblue is right. You should try 2.5GHz network.