db_constraint = False to solve deployment problem?

input/models.py

@@ -76,7 +76,7 @@ class Project(Volunteer):
     insurance_technic = models.BooleanField(default=False, verbose_name='Technikversicherung Ausland')
     support = models.CharField(max_length=300, blank=True, null=True, verbose_name='Betreuungsperson und Vertretung')
     cost = models.IntegerField(blank=True, null=True)
-    account = models.ForeignKey('Account', on_delete=models.CASCADE, null=True, to_field='code')
+    account = models.ForeignKey('Account', on_delete=models.CASCADE, null=True, to_field='code', db_constraint = False)
     granted_from = models.CharField(max_length=100,null=True,verbose_name='Bewilligt von')
     notes = models.CharField(max_length=1000,null=True,blank=True,verbose_name='Anmerkungen')