bell mobility bell mobility cellular mailed a tablet unsolicited and then charge me for using it burlington burlington,ontario

I went to walmart, agreed to a basic cellphone plan of $20./24 month contract including a free phone, no mention of a free tablet as well.  immediately after the phone began working bell mobility centre, masonville, ont. called offering a free tablet which i refused.  Two weeks later bell mailed an unsolicited package containing a FREE tablet but no mention of any charges or contract if i kept it. 

I thought it was truly free and worked off the cell  phone.  then began a constant barrage of phone calls saying i owed money for the tablet.  After finally getting bell to cancel the contract they are now demanding 95.89 as a balance on the account i never knew about or ever agreed to. 

I mailed the tablet back the same day the account was cancelled, and i dont owe bell anything for something i never wanted, never was told about, and never agreed to.  I am 68 years old and fighting stage 4 cancer.  Please get bell off my back.