Problem with Outlook

Good morning guys,

Guys, I'm having a big problem with some user emails.

When the user sends an Email, the email goes normally. However, when the user checks the Email in “Sent Emails” the text sent is different, I will give an example.

User sent:
Good morning everything is fine?
Follows attached....

The person he sent it to will see the text normally.
However, if the user who sent the message checks the “sent emails” in their email box, random phrases appear.

Example:

The user sent:
Good morning everything is fine?
Follows attached....

He will see:

“Are we going out today?
Follows attached"

"Will you marry me?
Follows attached?"

Among others.

Has anyone ever experienced this??