"Couldn't load file functions/bar.mcfunction in functions directory."

I made two function files:

tag @e[tag="xf_selected"] remove "xf_selected"
tag @e[c=1] add "xf_selected"

and

tag @e[tag="xf_selected"] remove "xf_selected"
tag @e add "xf_selected"

And that’s it. I’ve tested the commands and they are valid. I get the following errors:

[Commands][warning]-Couldn't load file functions/selectentity/all.mcfunction in functions directory.


[Commands][warning]-Couldn't load file functions/selectentity/nearest.mcfunction in functions directory.

What’s wrong and how can I fix it? – I literally have nothing else in the pack except for the manifest (which seems to be working).