Not getting rewards for killing 100 monsters

this happened to me twice now. last time about 10 minutes ago. i had finished the quest for killing 100 monsters. i was gathering all resources, like food and iron and also clicked the chest of killing 100 monsters. the chest disappeared, the quest was reset but i did not get any rewards. maybe relevant: my food storage was full. please solve this! very frustrating not to get any rewards after so much hard work.