Bitfield and Union in C - strange results, C (gcc)

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#include  <stdio.h>
#include <string.h>

struct Message {
     unsigned int hour : 5;
     unsigned int minutes : 6;
     unsigned int seconds : 6;
     unsigned int day : 5;
     unsigned int month : 4;
     unsigned int year : 12;
     unsigned long long int code : 26;
};

union Msgdecode {
    long long  int datablob;
    struct Message elems;

};

int main(void) {
    
    long long int datablob = 131809282883593;
    union Msgdecode m;

m.datablob = datablob;

printf("%d:%d:%d %d.%d.%d code:%lu\n", m.elems.hour, m.elems.minutes,
    m.elems.seconds, m.elems.day, m.elems.month, m.elems.year,(long unsigned int) m.elems.code);

union Msgdecode m2;
    m2.elems.hour = 9;
    m2.elems.minutes = 0;
    m2.elems.seconds = 0;
    m2.elems.day = 30;
    m2.elems.month = 5;
    m2.elems.year = 2017;
    m2.elems.code = 4195376;

printf("m2.datablob: should: 131809282883593 is: %lld\n", m2.datablob); //TODO WHY does m2.datablob != m.datablob?! 
    printf("m.datablob:  should: 131809282883593 is: %lld\n", m.datablob);

printf("%d:%d:%d %d.%d.%d code:%lu\n", m2.elems.hour, m2.elems.minutes,
      m2.elems.seconds, m2.elems.day, m2.elems.month, m2.elems.year, (long unsigned int) m2.elems.code);

}

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Compilation time: 0.12 sec, absolute running time: 0.14 sec, cpu time: 0 sec, memory peak: 3 Mb, absolute service time: 0,26 sec