This is not a bug, but your misunderstanding of these bonuses: levels 25-29 give 2% bonus total, not each. For more details, please see here, below the bonuses screenshot.

I do not agree. The total attack value has not changed. Not even a little

While from level 24 and 25 I noticed an increase in defense attack

At least here do you agree that they should change the values?

I also point out that sometimes it does not give a correct reading of the actual attack or defense power.

Rosario Runza said:
I do not agree. The total attack value has not changed. Not even a little
While from level 24 and 25 I noticed an increase in defense attack

Exactly, because level 24 doesn't give a def bonus and level 25 does. In comparison, level 25 and 26 give the same bonus, i.e., 26 doesn't give more bonus than 25, so there is no increase.

Please, read the explanations I wrote on that link that I've provided above.

Rosario Runza said:

At least here do you agree that they should change the values?

43.12 off for SotLs is ridiculous. It would be nice to know how to reproduce it, so I can report that one as a bug. However, I suspect it's an old(ish) bug that simply shows the wrong values in the training window, and that "43.12" belongs to some other units (maybe your Bonnies have 43.12 def?).

Okay, so at this point I will not strengthen the levels 27/28/29/30 ... I don't like it!

Thanks for the answer, you were very kind.

Rosario Runza said:

Okay, so at this point I will not strengthen the levels 27/28/29/30 ... I don't like it!

You will with level 30 (you get 5% instead of 2%). It's very questionable if it's worth it, but - like I wrote on that other topic - it might be for huge armies.

Rosario Runza said:

Thanks for the answer, you were very kind.

Happy to help.

I have read your explanation from the link above. Unfortunately (due to my ignorance) I have to use google translate. If on 191 million attack there is no increase, then something is wrong with the game. What is the meaning of 2% at each step? Only 5% were given at level 30 and stop. Out of 190 million, 5% is 9.5 million. But I have to receive the bonus step by step up to 9.5 million final. Or not? 9.5 million divided by 5 is 1.9 million. Instead I received zero (Ø). It will be google translate that doesn't translate well and we don't understand each other :) Anyway thanks.

I speak Italian.

Ok, now I say step by step what I did and then you tell me if it is correct.

1st step) level 24 I noticed increased attack (I don't remember how many millions I had)

2nd step) level 25 I noticed increased attack + defense (I have 164 million attack)

3rd step) I took trophy level 159 (caravel) and won 27 million attack. (164 + 27 = 191 million)

4th step) level 26 I noticed zero attack increase.

Everything is OK? If you tell me it's right then I don't talk anymore.

I don't want to be right, I just want to understand :) hello.

«If you don't like something change it; if you can't change it, change the way you think about it».

Mary Engelbreit

Rosario Runza said:

1st step) level 24 I noticed increased attack (I don't remember how many millions I had)

Yes. Lumber yard level 23 has no bonuses and level 24 gives 2% on offence, so you gained offence bonus.

Rosario Runza said:

2nd step) level 25 I noticed increased attack + defense (I have 164 million attack)

Level 24 has 2% offence and level 25 has 2% offence and 2% defence. So, you gained defence bonus, but not offence because that one didn't change (it was 2% and it remained 2%).

Rosario Runza said:

3rd step) I took trophy level 159 (caravel) and won 27 million attack. (164 + 27 = 191 million)
4th step) level 26 I noticed zero attack increase.

Correct. Level 25 has 2% offence and 2% defence, exactly as level 26 (2% offence and 2% defence), so there was no increase in the bonus.

Rosario Runza said:

Everything is OK? If you tell me it's right then I don't talk anymore.

Yes, that's how it's supposed to work. To summarise it:

So, you only gain new bonuses with levels 24, 25, and 30 (see the third column).

Rosario Runza said:

I don't want to be right, I just want to understand :) hello.

That is perfectly ok, and I want to explain it so it's clear.

If you need further explanation, I can ask for an Italian speaking person in Plarium.

Rosario Runza said:

«If you don't like something change it; if you can't change it, change the way you think about it».
Mary Engelbreit

Wise. 

Thank you! 

By "each step" I mean "for each level". Let us look at one gold mine and defensive bonus

Levels 1-23 give no bonus.

Levels 24-29 give 2% bonus

Level 30 gives 5% bonus.

What is important to notice is that these are total bonuses, and not increases! So, you gain no additional bonus for levels 25-29, and when you get to level 30, your bonus is 5%, not 2%+2%+2%+2%+2%+2%+5% = 17%!

This is the same as with production: each level has displayed total production and total bonus, not increases compared to the previous level.

Let's use this for reference:

To make it simple, let's say you have 100M defence with no other bonuses, and you only have one gold mine.

When you build your gold mine to level 23, that defence is 100M and the production is 800p/h.

When you build to level 24, the defence rises to 102M (100M + 2%) and the production goes to 900p/h.

When you build to level 25, the defence remains at 102M (because it is still 100M + 2%) and the production goes to 1000p/h. This is because "1000p/h, 2% off bonus, 2% def bonus" are total bonuses and production, and not the increase compared to the previous level.

Same for levels 26-29.

Then, when you build to level 30, the defence rises to 105M (100M + 5%), and the production goes to 1400p/h (again: "1400p/h, 5% off bonus, 5% def bonus" are totals!).

I hope this is clearer now. If it is still unclear, please tell me what your native language is and I'll try to see if Plarium has someone who can explain it in that language.