the horde event stopped working on my server map when I removed and put the mod back, now you can only spawn by command, the event never activates, help please.

What version are you using?

Also can you run the /debugHordeEvent command and send the file it generates?

Minecraft 1.19.2
The-Hordes-1.19.2-1.1.5d

net.smileycorp.hordes.common.hordeevent.capability.HordeSavedData@5a45b13[levelTime: 607225, nextDay=460]
Existing events: {
OngoingHordeEvent@2ed1e77a[player=YankeeMx, isActive=false, ticksLeft=0, entityCount=0, nextDay=460, day=0]
entities: {}
OngoingHordeEvent@4cd39d91[player=SwaggerMx, isActive=false, ticksLeft=0, entityCount=7, nextDay=460, day=0]
entities: {
ZombieVillager@2712, Zombie@271e, Zombie@271f, Zombie@26af, Zombie@26bb, ZombieVillager@26c4, }

You could probably update to 1.19.2-1.2.0 which may fix your issue, as it has a few bugfixes for the horde event but it also has a reset command which might just fix your player data, as for the server data, I don't know how it's got that desynced by removing the mod, but I will investigate it.

You can fix it on your server by going into your world folder and deleting hordes_HordeEvent.dat in the data file, which should fix the world data.