You have completed all at least 30 credits of approved course work (the required number of credits for your particular program), but you haven't paid all of your required installments yet and you don't want to graduate. What are your options?
You can continue to take courses - as long as you are paying tuition installments, you are eligible to continue taking courses. All courses must be approved by your graduate advisor and must be relevant to your program of study. Note, however, that these courses are considered part of your degree and can not be transferred to another degree or program.
It may be possible to upgrade your scale, but you should check their regulations with TQS directly, including -- but not limited to -- reading their web site (http://www.tqs.bc.ca/).
Another option for you is to just sit back and pay your installments as they are due, not worrying about anything else. If you do this, keep track of how many installments you have left, and when you are ready to pay your final one, deal with graduation then.