That happens because when the amount of cryptocurrency is distributed from the exact Launchpool to the users, that Launchpool transfers into the Inactive section.
You may control how much time is left for a certain Launchpool by clicking on the details. 
After that, you should press on the sum opposite the Ends in phrase. 
https://biswap.org/pools/stake_bsw
After you press on that amount, you will be automatically transferred to BscScan, where you can see how many days are left for that Launchpool.
All inactive Launchpools are available on the Launchpools tab. Click the Inactive button to find the Launchpool that has already allocated its token rewards.
You may withdraw your income and staked tokens at any time by clicking on the minus(-) button. 