Impossible to load any datapack in my 26.1.2 [java] server with Fabric

I have try to install some datapacks for my small server but when i lunch it, it give this :

Following by hundreds of error, for example:Console:
Starting net.fabricmc.loader.impl.game.minecraft.BundlerClassPathCapture
Main/INFO:
Loading Minecraft 26.1.2 with Fabric Loader 0.19.2 Mappings not present! Loading 55 mods:
[...]

Following by hundreds of error lines, for example:

Console:

Failed to load function unlock_all_recipes:grant_recipes
main/ERROR:

java.util.concurrent.CompletionException: java.lang.IllegalArgumentException: Whilst parsing command on line 2: Unknown or incomplete command. See below for error at position 0: <--[HERE]
[...]
Caused by: java.lang.IllegalArgumentException: Whilst parsing command on line 2: Unknown or incomplete command. See below for error at position 0: <--[HERE]
[...]

I ask to an AI and it tell me that Fabric does not yet properly recognize this version, which prevents datapacks and .mcfunction files from loading.

Thank you for your help