How can I contact Customer service ASAP

I used koodo over 2 months ago whist I was in Canada. Being an international student I had to leave Canada and go back to Africa for summer holidays. Since Koodo had delayed my callback and the cancellation of my line (which only happens via call backs, I tried visiting the shops and calling customer service but that dint help) after tons of trial i finally cancelled the number a few hours before my international flight. thats when I learnt I had some old up , I had some money from my previous bills to pay. I unfortunately did not have any Canadian dollars left in my card (due to travelling I had also frozen my canadian cards for the time being) I later went to a Telus shop and spoke to customer service agent about this and told them my issue on how I would not be able to pay until September (when I come back to Canada for school and unfreeze my cards. They told me that the credit for late payment will increase but other than that its all ok. To double check I even spoke to a Cutomer service lady via phone and they told me the same thing. Now I am miles away unable to communicate with any koodo assistants and now I am getting emails saying that my account is going to be forwarded to the collection agency, this is unfair and really stressing, I have no clue what to do. I would appreciate some assistance as soon as possible please.