diff --git a/src/displace_atoms.cpp b/src/displace_atoms.cpp
index 5ecf5a2c9e..d5b6c1b9af 100644
--- a/src/displace_atoms.cpp
+++ b/src/displace_atoms.cpp
@@ -74,8 +74,7 @@ void DisplaceAtoms::command(int narg, char **arg)
   // group and style
 
   igroup = group->find(arg[0]);
-  if (igroup == -1) error->all(FLERR,"Could not find displace_atoms group ID");
-  groupbit = group->bitmask[igroup];
+  groupbit = group->get_bitmask_by_id(FLERR, arg[0], "displace_atoms");
 
   if (modify->check_rigid_group_overlap(groupbit))
     error->warning(FLERR,"Attempting to displace atoms in rigid bodies");
diff --git a/src/dump.cpp b/src/dump.cpp
index 3425b6d441..b6d8cf535a 100644
--- a/src/dump.cpp
+++ b/src/dump.cpp
@@ -58,7 +58,7 @@ Dump::Dump(LAMMPS *lmp, int /*narg*/, char **arg) :
   id = utils::strdup(arg[0]);
 
   igroup = group->find(arg[1]);
-  groupbit = group->bitmask[igroup];
+  groupbit = group->get_bitmask_by_id(FLERR, arg[1], fmt::format("dump {}", arg[2]));
 
   style = utils::strdup(arg[2]);
 
@@ -311,6 +311,7 @@ void Dump::init()
 
 int Dump::count()
 {
+  // group all
   if (igroup == 0) return atom->nlocal;
 
   int *mask = atom->mask;
diff --git a/src/fix.cpp b/src/fix.cpp
index 8678706347..3f3b585e0a 100644
--- a/src/fix.cpp
+++ b/src/fix.cpp
@@ -48,8 +48,8 @@ Fix::Fix(LAMMPS *lmp, int /*narg*/, char **arg) :
     error->all(FLERR,"Fix ID must be alphanumeric or underscore characters");
 
   igroup = group->find(arg[1]);
-  if (igroup == -1) error->all(FLERR,"Could not find fix group ID");
-  groupbit = group->bitmask[igroup];
+  if (igroup == -1) error->all(FLERR,"Could not find fix {} group ID {}", arg[2], arg[1]);
+  groupbit = group->get_bitmask_by_id(FLERR, arg[1], fmt::format("fix {}",arg[2]));
 
   style = utils::strdup(arg[2]);