Avangatee Services, LLC Told me my computer was safe from virus for life, my computer was infected today. San Leandro California

I paid 3989 dollars to this company and was guarenteed my computer would be safe for life, tonight my computer was infected with numeral viruses and I had to pay additional amount to Microsoft Security to get my computer fixed and was told that no company can guarentee protection for life.  When I contacted Avangatee Services, LLC for a full refund they stated I could not get a refund due to the fact that I used their service and that they told me I was suppose to contact them once a month; which they never stated when I signed up.