added

After applying rank of 8 the progress was expected to be 51, but was actually 50. In logs the rank of account is 7 and the rank of task is 8 so the progress must be +10 but as I understand it says that the progress must be +11. Is it my fault or there are test issues?

You're right, assuming progress is not set outside of the User class, the solution should work fine. This can be fixed by changing progress into a property that can only be set privately.

Seriously, how was this kata even published?

Javascript has no Solution Setup os Sample Test Cases.

Much like C# had these items missing until a few hours ago. (08.JAN.2023 @ 03:15 GMT-3)

This assume that the class... erm... User will be well behaved to always call the right method.
Something like:

var user = new User();
user.progress = 10099;
user.incProgress(-8);

Would break the code.

Going through the languages...

• CoffeeScript needs sample tests
• C# was just fixed.
• I'm pretty sure Haskell dosn't have random tests (may be wrong tho)
• Java needs sample tests
• Python needs to be updated.
• Ruby needs sample tests.

not anymore ;)

Not only the Sample Tests, but the whole Solution Setup.
Is the coder suppose to divine what the kata wants to ingest?
Classes, methods, properties.. the whole shebang.

fixed (reset trainer)

It's not broken. The test cases still work. But you are correct, sample tests are missing.

As of 07.Jan.2023 the C# has no Solution Setup or Sample Test Cases.

I fear that the C# translation of this Kata is broken beyond repair.

You misterpreted the description.
The key IS repeated throughout the message, but you don't need to make them the same length.
A little bit of modulo math.. et voíla!

Why even use fill?
It can be solved in O(n), in a single passage.

I have to agree with some of the commenters.
Yes, this is a nice short piece of code.
However, as performance and scalability goes it is, sorry to use such forceful words, a piece of crap.
It runs in O(n²), when this problem is solvable in O(n).