You will need to contact customer support to have the line temporarily suspended.
A few things to note:
The link provided above by @NaliniR for all the different methods to contact customer service is correct.
The $10 fee only applies to transactions that can be done on select transactions available on Fido MyAccount self-serve. for a list of all the administrative charges see here.
A temporary suspension can only be done by a Fido representative so you will not be charged the $10 fee, feel free to contact them through any of the available methods listed in the link provided above.