Incorrect syntax highlighting

[its-the-shrimp]

I'm not sure where's the root of the problem so I figured I'd first ask here: I've recently updated both Neovim and rust-tools, after which syntax highlighting in Rust started working better as it started to recognise highlight identifiers, function calls, constants, etc. more appropriately, instead of just colouring most of the code with Normal, as was the case before that, but one problem is that now it doesn't recognise doc comments correctly, confusing them for normal comments, here's how it looks like:

But if I select the doc comments, they get coloured correctly:

Also, when writing a doc comment, for a moment it's coloured with the correct colour, but a moment later it gets erroneously recoloured as if it was a normal comment.

Here's how rustCommentLineDoc syntax item is defined for me, along with how it's coloured:

And here's how rustCommentLine syntax item is defined:

I suspect that it has to do something with the defined syntax items, but I have no idea beyond that, how can I fix that or where can I look for a possible solution? Any help is deeply appreciated