Some characters are suppressed when the bibliography is created

Hello,

In my PhD, I use references like that [MAR98].

Until now, there wasn’t any issues.

From yesterday, i obtain this :

see first attachement

So the first bracket that is to say this character “[”" is suppressed.

Here you can see how output style is tuned

See second attachement

How can I do so as to suppress this porblems of brackets ? Moreover, I noticed that with another computer but with the same style I didn’t have this problem.

Thank you for your help

issue.gif
output style.gif