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Mismatch in TM

Hello!
My name is Alícia and I am a Translator based in Brazil. My agency is Lítero, in Rio de Janeiro.
I have a problem about mismatch in SDL Trados 2019. 
Firstly, I tried to find a Fórum about this subject, but I could not found. 
 
In my translation memory, several words/phrases are not matching with the correct translation which is already saved in the memory. I keep updating them, but then, from time to time, they come back to be wrong once more.
 
Should I just keep updating or there is something else I should do?
 
Kind regards,