why is there no POS reward today
More information is needed to answer your question.
How many coins?
When were they put?
When was the previous reward?
the last reward was a day ago, on a wallet of 25,000 and a stakinklab of 25,000, there was no reward anywhere
It is possible that the weight of the network is growing, and your share is decreasing, the last time there are a lot of new wallets with a lot of coins! I also did not get a stack today, in one of the 25k coin wallets.
about stakinglab. they might have some kind of update, so there was no stack