Hello Therecould i please get some help for me , how i can trade...

Hello There
could i please get some help for me , how i can trade my share from US market i used to hold CBR share on OCT and i went overseas also same time i moved in to new address and forget to change the address in to Comsec account as i thought i changed the address in to CBA it will be change all ...as overseas i did not check my share account when i got back i did not see my share holding and rang to Comsec and they told me all the history and they gave me US computer share to contact also they told me to send them letter showing the proof of address change so they will send me another letter in to my new address, and still waiting from old address i am able to get letter but the code already expired..so do not know what to do..so could you please help me , what i need to do now at this stage