Fix https://github.com/bigprof-software/online-invoicing-system/issues/3#issuecomment-657208153
Fix https://github.com/bigprof-software/online-invoicing-system/issues/3#issuecomment-657208153

bigprof-software/online-invoicing-system,bigprof-software/online-invoicing-system,bigprof-software/online-invoicing-system