One wire problem

Hi, I am working with 1kb EEPROM DS2431 one wire device in connectcore W1-MX51 early availability board. I loaded the slave module first and then the master module [:(] . For reading/writing to the device, the 1-wire driver provides a binary attribute inside the sysfs. In the case of the DS2431, this attribute is placed under the following path and with the following attributes
ls /sys/devices/w1_bus_master1/bus/devices/2d-0000015db4d0/
The 2d-0000015db4d0 is the unique device id that will appear after the master detects the slave device.
In my case I connected two devices in parallel but only one device is detected in sysfs.
I googled but I didn’t find any clue why the 2nd device is not detected.
Did I miss anything?

Thanks in advance for your help.