Like people stated above, only way to cancel is by phone customer service or visiting the location. Make sure to return the optimum belongings hardware such as modem or router if haven't paid in full, otherwise fees will be applied. Also be aware if you have a plan and didnt finished it completely you'll have to pay additional fees for each month remaining for breaking the contract commitments.
No Call them
No, you have to call or go to one of their locations
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