Materials for Epheria Sailboat disappear during crafting

Hi
My materials for Epheria Sailboat disappeared during crafting. When I start building it all the materials are in the storage and then I let my workers start working on them. After a few days some of the materials just disappear, I am pretty sure I have enough materials in my storage and I didn't move them. They just disappear to nowhere. Please help!

 

Dont forget that for Epheria sailboat 1 material is equal to one task. If sailboat require for example 1000 plywood, that means u need to let workers do this task 1000 times.

 

Please check this:
https://cdn.discordapp.com/attachme.../487663964356870149/Give_me_back_my_steel.gif
I lost 2 sailboat designs, 40+ standardlized timber square, 20 steel and 3 flax farbic just like that.

 

Go to the workshop, where you make sailoat. Click on it and you should have details how many items have you already processed. As i mentioned earlier, you probably didnt lost it. This items were added to overal sailboat making process
On this gif you have ordered 2 workers to repeat 2 tasks. They took 2 items to complete this tasks. For sailboat you need to use overal 600 steel. That means you need to make the same 598 times till the process will be over.

Making epheria sailboat is totaly different from regular crafting. When crafting other items 1 worker gets all the items and craft something. While making sailboat 1 worker takes only 1 material per 1 stamina used and build up to their pool.
So according to steel at beggining its 0/600. After those 2 workers took 2 steel its now 2/600.