Am I doing something wrong?

I don?t want to think of how many coins I?m wasting doing as many deliveries as possible trying to get expansion parts. I?ve done easily upwards of 50 today and yesterday and I?ve gotten
1 mine pick
1 white paper expansion part
~8 or so blue trash bags from the current event but I don?t use them so idc
1 mine shovel

I thought this was supposed to be the ?boosted deliveries? event?? Am I doing something wrong?

Thanks in advance