Arduino Serial Monitor displaying weird characters and changes spelling
Your code for the most part looks ok. Your symptoms indicate a Baud mismatch or the receiver is not getting all of the bits. Try doing without the delay's, even reducing them may help. Note when in a delay the processor is committed and cannot do anything else.  See if that helps. 115000 baud is quit hot for the Arduino and software serial. Maybe you can slow things down a little and see if that helps.