No after sales service

I bought 3 Smart Geyser Switch + Energy Consumption Monitor | 63A, 230VAC | WiFi Tuya Smart Life and have installed 2. 1 on the main incoming supply and 1 on my geyser. Both are reading substantially less current(and power) than what is actually being used so as a power meter they are useless. The initial service(delivery )was quick but I have for about 2 weeks tried to contact Henractech via email, whatsapp and phone to no avail. Also not having a battery for when there is loadshedding when the power goes off so does the meter and any schedule falling in that time does not work and when power back on the meter defaults to on. The return period of 14 days is also now passed but all irrelevant if they dont answer their phones. There are better places to shop