Thanks for the comments and sorry about the missing information about my setup.
I use plastic tubs with under tank heat mat, I place the thermometer on the floor of the tub at the middle of the warm side.
With the first thermostat I can control the temp I want it to be: (sorry, tried to insert image directly but nothing seem to happen so I put a link)
https://ibb.co/emzRgm
And with the second thermostat I can only choose what temp I want to be the maximum then it lower the temp few degrees and turns on again.
https://ibb.co/dECU1m
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