every time an enemy hits a building a crash log like this appears, no clue why though

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FATAL ERROR in
action number 1
of Other Event: User Defined 0
for object obj_article_parent:

second index out of bounds request 0,6 maximum size is 1
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--------------------------------------------------------------------------------------------
called from - gml_Script_print_debug (line 5)
called from - gml_Script_vm_gml_thread_exec_slice_call_fn0 (line 5)
called from - gml_Script_vm_gml_thread_exec_slice_call (line 4)
called from - gml_Script_gml_thread_exec (line 706)
called from - gml_Script_gml_program_call (line 16)
called from - gml_Script_ugc_script_call (line 27)
called from - gml_Script_article_step (line 1)
called from - gml_Object_obj_article_parent_Other_10 (line 2)
called from - gml_Script_AdvanceGameFrame (line 36)
called from - gml_Script_NetworkAdvanceFrame (line 201)
called from - gml_Object_NetworkManager_Step_0 (line 231)