Happy to help! 
Self Serve Steps: https://selfserve.publicmobile.ca/
1) To change to a different plan immediately: Overview - Plan and add-ons - My plan - Change plan - Chose the plan you want - Change plan now - Yes change my plan;
IMPORTANT: Before proceeding, please note that:
The change will take effect immediately.
Any payments you've made on your current plan cannot be applied towards your new plan.
2) To change to a different plan at renewal: Overview - Plan and add-ons - My plan - Change plan - Choose the plan you want - Change on next renewal date - Yes change my plan.
Your new plan will take effect on your next renewal date and you won't be charged until then. This change replaces any other future-dated plan changes. After changing your plan, you will lose your current promotion.
***If you want to contact a moderator:
Submit a ticket via the 24/7 virtual assistance SIMon to get this looked at
Note that you will need to create and/or sign in to the Community for the below link to work.
SUBMIT A TICKET - https://www.publicmobile.ca/en/bc/get-help
@Alcoverecording Very strange, I have just tried and have no problem changing my plan. Try to clear browser's cache, use different browser, use Private / Incognito mode, turn off ad blockers. I f you are still experiencing problems after that, you will need to send a private message to a Moderator_Team, they will help to resolve your problem!
Here is the link: click here
In your message, please provide your name, Public Mobile account number or phone number and PIN.
Good luck! 
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