Hi @Channara , please also read these:
I am not sure about your implementation but a SEQUENTIAL of 4 digits means 10000 values (from 0 to 9999) and this can be very low in most of the implementations. As per what was explained by @vgarciabnz (and linked in the docs) if you would have 100 devices this means that after the initial synchronization of your devices you would have exhausted all the values!
100 devices x 100 reserved values
So you probably want a higher value.