Fail to read the temperature, humidity and light intensity when relay active

Using Arduino Programming Questions
21

Yes, because in the coding, I switch off everything except that.

22

Ok and the wire length?

23

approximately 80 cm for the lcd and 50 cm for both sensors

24

Well that is a big problem.
I2C was not designed to drive long wires, or multiple long wires and those long wires are also quite susceptible to EMI

25

ohhh I just found that out, thank you for the knowledge sir, later I will try to shorten the cable.
if there are still problems later I will reply again in your comment hehehehe

26

In general a good idea.
You also might try slowing down the I2C clock
Wire.setClock(10000)