when creating a minecart track side by side, even with 1 block different in y axis the track still connected in x axis at the start and end of the track, but the middle parts are fine if the rail were placed from the middle

this can be resolved by making one track at least 1 block longer at the end and start then create another track from the actual start and end, then destroy the exceeding rail from the first track
this way the rail wont be connected in x axis at the end and start of the track