The temporary structural bridge came crashing down in Sandton in October last year, killing two people and injuring 19 others.
The Department of Labour says those involved have not handed in all the required documents.
This is the third time the enquiry into the M1 structural collapse has been delayed.
The department’s acting spokesperson Mokgadi Pela says they've made some progress in gathering reports from those involved.
The department’s acting spokesperson Mokgadi Pela says they've made some progress in gathering reports from those involved.
