Game always crashes when trying to load Lucario in a 1v1 Online Match:

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ERROR in
action number 1
of Step Event0
for object sentry_handler:


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FATAL ERROR in
action number 1
of Step Event0
for object cs_playerbg_obj:

Unable to find any instance for object index '-4' name '<undefined>'
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called from - gml_Script_get_instance_x (line 2)
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 712)
called from - gml_Script_gml_program_call (line 16)
called from - gml_Script_ugc_script_call (line 27)
called from - gml_Object_cs_playerbg_obj_Step_0 (line 75)

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called from - gml_Script_catcherror_update (line 6)
called from - gml_Object_sentry_handler_Step_0 (line 5)