Shall I say
- I have tried to send you the money but it has not worked.
- I have tried to send you the money but it does not work.
I think first version is the best because all my essay did not work.
Since you use Present Perfect in the first part, using Present Perfect in the other sounds a bit better -- they both explain the actions that happen in the past, and now we have the results of them, and the exact timing is not important.
It is fine to use Present Indefinite in the second part too, the meaning changes slightly, though. With
I have tried ..., but it does not work.
you make an assumption that whatever obstacle there was that prevented the money from arriving, is still in effect, still present.
If you say
I have tried ..., but it has not worked.
you only state that no "try" was a success, and the current condition of money's not being where you intended it to be. The obstacle may have been eliminated since your last try, and there is no way to know except to try again.
In American English I think "I tried to..." sounds better.
I tried to send you the money, but it didn't work.
It depends on the time reference: if it's something that has just happened:
I've just tried to send you the money but it hasn't worked.
Adding "just" makes it right, without it you should just use the simple past.
If you are using a machine not working properly you could say:
I've just tried to send you the money but the machine isn't working
If you are still trying you could say:
I'm trying to send you the money, but the website appears to be broken.
If you tried many times, until now, you could say:
I've been trying to send you the money since this morning , but the website is dead.