If you're seeing unscheduled games – either NOT YET SCHEDULED or NO POSSIBLE TIME SLOTS – that's typically due to constraints or because you don't have enough time slots to fit all your games.
Think of this as an iterative process.
Especially if you have a lot of unscheduled games, you probably want to diagnose the issue and see if you can get the allocator to schedule more of them before resorting to manual work.
Re-run the allocation or regenerate the schedule.
As a first step, you can try simply re-running the allocation process to see if it does better on a second attempt (i.e. hitting retry allocating games and if that doesn't improve things erase games and re-generate the whole schedule – this will give you new pairings, which may or may not unclog some blocks resulting from the way teams are matched up).
Persistent Unscheduled Games
Focus on specific weeks.
You can also lock weeks that are fully allocated > retry allocating > see if any more weeks got fully allocated > lock those > repeat. (It can take several attempts to get before another week is fully allocated. If you see no progress after 5-10 attempts, you should consider a different approach.)
Similar to the above, you can also just click the re-allocate button on individual weeks one at a time.
Try dragging a game to an available time slot and see what the error says.
Make sure your free slots are visible:
If you don't see that button, you have no free slots. Your problem is likely that you have too few time slots to fit all your games.
Free slots will show in green:
Try drag-n-dropping a game into one of those available slots. It will tell you if and why the game cannot be scheduled there. This will give you a clue as to what is the issue. Maybe a constraint is set up incorrectly, blocking something you didn't intend to block.
If the error message shows you some constraint violation you're happy to ignore (e.g. a team requested to start a few minutes after the scheduled start time) you can click save on that error message to execute the change and ignore the violation.
Manually schedule games.
If you've tried all of the above and you only have a handful of unscheduled games left, you may just want/need to schedule them manually. Some things are easier for a human to untangle than for the algorithm. And in some cases, you may just want to ignore a constraint (see paragraph above).
It will not move games to different weeks.
Note that, for leagues, allocating games does not move the games outside of the weeks they are in. If you see NO POSSIBLE TIME SLOTS, no amount of reallocations will help.
You may want to
manually move those games to other weeks and then retry allocating, or
manually put them somewhere and override the constraint warning, or
swap weeks around (e.g. swap games from weeks 1 and 2) or
swap schedules of specific teams (e.g. if Team A needs a Bye in Week 1, but the team with the Bye in Week 1 is Team B).
or try tournament mode (see below)
Try switching to tournament mode
In some cases, using the tournament scheduler is a better solution. For instance, if your time slots are not evenly spread across weeks or if certain teams can't play in certain weeks. The tournament scheduler is not bound by weeks, so that added flexibility can help.
You can find the button to switch between league and tournament mode by clicking the little arrow next to the Copy Season button.
Note that this might require some other tweaks (e.g. setting the minimum time between games to a few days to make sure any team's games aren't bunched together).
The system will automatically switch you back to the correct mode once you click publish schedule.
Ask for help
Unfortunately, scheduling is not easy – some trial and error are involved and certain scenarios just might not be feasible. Let us know if you have any questions about all of this or if you'd like to engage our services under our full-service agreement and have us take a stab. We can't guarantee a solution in these cases unfortunately – we can only do the same things described above; some schedules can be too complex to solve or may require large amounts of manual work, which we may or may not have the bandwidth for (and either way, we'd let you know before going down the rabbit hole) – but we can try all the normal things and let you know where you're at.