diff --git a/doc/environments/groupthm/groupthm.dtx b/doc/environments/groupthm/groupthm.dtx
index 22ae60f..f85e2aa 100644
--- a/doc/environments/groupthm/groupthm.dtx
+++ b/doc/environments/groupthm/groupthm.dtx
@@ -1222,16 +1222,16 @@
 % Remove properties from hooks
 %
 %    \begin{macrocode}
-    \hook_gremove_code:nn { @@/prename  }
-    \hook_gremove_code:nn { @@/postname }
-    \hook_gremove_code:nn { @@/mapname  }
-    \hook_gremove_code:nn { @@/thmtools }
+    \hook_gremove_code:nn { @@/prename  } { #1 }
+    \hook_gremove_code:nn { @@/postname } { #1 }
+    \hook_gremove_code:nn { @@/mapname  } { #1 }
+    \hook_gremove_code:nn { @@/thmtools } { #1 }
 %    \end{macrocode}
 %
 % Remove theorem group from list of defined theorems
 %
 %    \begin{macrocode}
-    \clist_remove_all:Nn  \g_@@_defined_theorem_groups_clist { #1 }
+    \clist_gremove_all:Nn  \g_@@_defined_theorem_groups_clist { #1 }
 %    \end{macrocode}
 %
 % Now, unset all relations with all defined theorem groups in the internal hooks.
@@ -1239,27 +1239,27 @@
 %    \begin{macrocode}
     \@@_hook_gset_rule_foreach:nNnn
       { ?? }
-      \g_@@_defined_theorem_groups_clist { #1 }
+      \g_@@_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \@@_hook_gset_rule_foreach:nNnn
       { @@/prename }
-      \g_@@_defined_theorem_groups_clist { #1 }
+      \g_@@_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \@@_hook_gset_rule_foreach:nNnn
       { @@/postname }
-      \g_@@_defined_theorem_groups_clist { #1 }
+      \g_@@_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \@@_hook_gset_rule_foreach:nNnn
       { @@/mapname }
-      \g_@@_defined_theorem_groups_clist { #1 }
+      \g_@@_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \@@_hook_gset_rule_foreach:nNnn
       { @@/thmtools }
-      \g_@@_defined_theorem_groups_clist { #1 }
+      \g_@@_defined_theorem_groups_clist
       { unrelated }
       { #1 }
 %    \end{macrocode}
diff --git a/doc/environments/groupthm/groupthm.sty b/doc/environments/groupthm/groupthm.sty
index b4c1f55..6126871 100644
--- a/doc/environments/groupthm/groupthm.sty
+++ b/doc/environments/groupthm/groupthm.sty
@@ -156,34 +156,34 @@
 \cs_new:Npn \__groupthm_undeclare_theorem_group_aux:n #1
   {
     \cs_undefine:c { __groupthm_use_group_#1:   }
-    \hook_gremove_code:nn { __groupthm/prename  }
-    \hook_gremove_code:nn { __groupthm/postname }
-    \hook_gremove_code:nn { __groupthm/mapname  }
-    \hook_gremove_code:nn { __groupthm/thmtools }
-    \clist_remove_all:Nn  \g__groupthm_defined_theorem_groups_clist { #1 }
+    \hook_gremove_code:nn { __groupthm/prename  } { #1 }
+    \hook_gremove_code:nn { __groupthm/postname } { #1 }
+    \hook_gremove_code:nn { __groupthm/mapname  } { #1 }
+    \hook_gremove_code:nn { __groupthm/thmtools } { #1 }
+    \clist_gremove_all:Nn  \g__groupthm_defined_theorem_groups_clist { #1 }
     \__groupthm_hook_gset_rule_foreach:nNnn
       { ?? }
-      \g__groupthm_defined_theorem_groups_clist { #1 }
+      \g__groupthm_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \__groupthm_hook_gset_rule_foreach:nNnn
       { __groupthm/prename }
-      \g__groupthm_defined_theorem_groups_clist { #1 }
+      \g__groupthm_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \__groupthm_hook_gset_rule_foreach:nNnn
       { __groupthm/postname }
-      \g__groupthm_defined_theorem_groups_clist { #1 }
+      \g__groupthm_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \__groupthm_hook_gset_rule_foreach:nNnn
       { __groupthm/mapname }
-      \g__groupthm_defined_theorem_groups_clist { #1 }
+      \g__groupthm_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \__groupthm_hook_gset_rule_foreach:nNnn
       { __groupthm/thmtools }
-      \g__groupthm_defined_theorem_groups_clist { #1 }
+      \g__groupthm_defined_theorem_groups_clist
       { unrelated }
       { #1 }
     \__groupthm_remove_from_theorem_group_ordering:n { #1 }
@@ -193,7 +193,7 @@
     \cs_if_exist:cTF { __groupthm_use_group_#1: }
       {
         \msg_error:nnnnn { groupthm } { wrong ~ definition }
-          { group } { #1 } { already }
+          { theorem ~ group } { #1 } { already }
       }
       {
         \__groupthm_declare_theorem_group_aux:nnnnn { #1 } { #2 } { #3 } { #4 } { #5 }
@@ -209,7 +209,7 @@
       }
       {
         \msg_error:nnnnn { groupthm } { wrong ~ definition }
-          { group } { #1 } { not }
+          { theorem ~ group } { #1 } { not }
       }
   }
 \cs_generate_variant:Nn \groupthm_renew_theorem_group:nnnnn { n V V V V }