Terrible service and false product advertising

I bought an RCT Megapower 1KVA/1000w inverter in July last year from Avo, the inverter never reached the point where the power had drained from the unit and after about 3 to 4 month the inverter would barely last 45 minutes even if nothing was plugged in, I contacted a few places to get pricing on Lithium Ion replacement batteries ,when I finally found a replacement battery I was advised that the until cannot be set to a different charge voltage to accomodate a Lithium Ion battery without damaging the battery , at no point was there anything in the manual or on the product indicating its lack of compatibiliy with other battery types ,whereas most online retailers clearly stipulate whether or not the unit is compatible with Gel,Lithium or Lead batteries.

I logged the case in November after some back and forth with Avo and eventually my faulty inverter was collected on the 8th of December, I asked for updates and was told to wait 7-14 working days which we have obviously far surpassed in wait time, I have been ignored repeatedly and the service is absolutely deplorable , I expect a full refund for the false advertising of the unit compatibility as well as the abismal services.

I have also confirmed with the courier company that almost all of the RCT Megapower 1000w units have been returned so avoid them and Avo like the plague