Changing babel package inside the same document

I am currently writing my Ph.D. thesis in French and English. Following the procedure that I found here Changing babel package inside a single chapter, I have divided the document into two parts, one for the French one and one for the English one. It seemed to work fine when uploading the first French chapter. However, starting from the second Chapter LateX goes crazy looking like this:

I am using the following packages:

usepackage[latin1]{inputenc}
usepackage[T1]{fontenc}
usepackage{eurosym}
usepackage[french,english]{babel}

while the code concerning the French part looks like this:

begin{otherlanguage}{french}
     input{Chapter1_FR/Chapter1_FR}
     input{Chapter2_FR/Chapter2_FR}
end{otherlanguage}

I have tried to run the code with Chapter 2 only but it still gives the same output. What do you think could be the problem and how can I solve it?
Thank you a lot in advance!

P.S. at the moment there are no issues concerning the switch to English.