At this point, it is best for you to seek legal advice. Many states have air-tight laws that protect the rights of tenants. In those states, any notice "improperly" served for payment and/or eviction will render them useless and the number of days from one (notice) to the next to start again. The type of attorney you need is one who handles landlord/tenant matters which may also be "Google-able" under "evictions."
Best of luck to you.