Error on expense report Duplicate entry for key 'uk_ecm_files'

Using my Dolibarr HR modules
1

hi, I get this error for any user who tries to validate his expense report…
Do you know what can I do o fix it ?
I’m not a developer
thanks

Duplicate entry ‘expensereport/ABC2006000118-ABC2006000118.pdf-1’ for key ‘uk_ecm_files’