don't buy a phone from jet

i bought a new phone from jet High point last month its a Sumsung A2 core, the phone has been freezing for the previous two weeks and all the retailer is calling me and sending me threatening messages as to if i don't pay my account they will charge more interest and staff. i always pay my account on time, but what they doing is unacceptable on all levels, i have paid my account but the phone is still freezing just a month old