diff --git a/htdocs/compta/facture/class/facture.class.php b/htdocs/compta/facture/class/facture.class.php
index b5332b033ef..2a3f8b4a17f 100644
--- a/htdocs/compta/facture/class/facture.class.php
+++ b/htdocs/compta/facture/class/facture.class.php
@@ -4230,19 +4230,6 @@ class Facture extends CommonInvoice
 
 		$this->db->begin();
 
-		// Free discount linked to invoice line
-		$sql = 'UPDATE '.MAIN_DB_PREFIX.'societe_remise_except';
-		$sql .= ' SET fk_facture_line = NULL';
-		$sql .= ' WHERE fk_facture_line = '.((int) $rowid);
-
-		dol_syslog(get_class($this)."::deleteline", LOG_DEBUG);
-		$result = $this->db->query($sql);
-		if (!$result) {
-			$this->error = $this->db->error();
-			$this->db->rollback();
-			return -1;
-		}
-
 		// Memorize previous line for triggers
 		$staticline = clone $line;
 		$line->oldline = $staticline;
@@ -6441,13 +6428,38 @@ class FactureLigne extends CommonInvoiceLine
 			return -1;
 		}
 
-		$sql = "DELETE FROM ".MAIN_DB_PREFIX."facturedet WHERE rowid = ".((int) $this->rowid);
+		// Free discount linked to invoice line
+		$sql = 'UPDATE '.MAIN_DB_PREFIX.'societe_remise_except';
+		$sql .= ' SET fk_facture_line = NULL';
+		$sql .= ' WHERE fk_facture_line = '.((int) $this->id);
+
+		dol_syslog(get_class($this)."::deleteline", LOG_DEBUG);
+		$result = $this->db->query($sql);
+		if (!$result) {
+			$this->error = $this->db->error();
+			$this->errors[] = $this->error;
+			$this->db->rollback();
+			return -1;
+		}
+
+		$sql = 'UPDATE '.MAIN_DB_PREFIX.'projet_task_time';
+		$sql .= ' SET invoice_id = NULL, invoice_line_id = NULL';
+		$sql .= ' WHERE invoice_line_id = '.((int) $this->id);
+		if (!$this->db->query($sql)) {
+			$this->error = $this->db->error()." sql=".$sql;
+			$this->errors[] = $this->error;
+			$this->db->rollback();
+			return -1;
+		}
+
+		$sql = "DELETE FROM ".MAIN_DB_PREFIX."facturedet WHERE rowid = ".((int) $this->id);
 
 		if ($this->db->query($sql)) {
 			$this->db->commit();
 			return 1;
 		} else {
 			$this->error = $this->db->error()." sql=".$sql;
+			$this->errors[] = $this->error;
 			$this->db->rollback();
 			return -1;
 		}