No response from TEVO on dud product

I purchased a Bennett Read Swift Cordless Wet & Dry Vacuum in November 2019. I extended the 1 year warranty to a 2 year warranty. In July 2020 it stopped working. It was sent away to have the battery replaced. Again in April 2021 it stopped working and again the same process. Nowhere in the USER GUIDE does it mention frequent battery replacements. I called the TEVO Customer Service Help Line ***) to find out if this is a regular problem and if so, what do I do to prevent it. I was anxious to know how much the battery replacement would cost once the warranty has expired. The person who answered my call could not help me and suggested I speak to a technician at a different Help Line - ***. Again, the person who took my call could not help me but said she would put me through to someone who might. The phone rang for some time and a voice activated message said my call could not be answered and I could not leave a message. I was cut off. So I sent an email to TEVO. Two weeks later a second email. NO RESPONSE. I will never purchase a TEVO product again