Promised Best solar on the market and received equivalent of a small generator

Bought a 3kw Growatt off grid solar inverter for R 47 000 in September 2021. To date the inverter only offers solar power to a max of 1 1.2hrs if we lucky. We were assured the system would give power for 4-5 hrs. For the last 5 weeks I have been begging for a solution. Their responses, your lights are not haolgen change all bulbs +R3000. Then your outside lights are draining the power disconnect them, now no outside lights working ever. Then change your lifestyle when loadshedding is on, we are down to drawing solar for fridges, wifi and tv's and still solar power for only a max of 1 1/2 hrs. They said they will replace the system I have been waiting 11 days with no assistance. I did not buy an expensive system to only have 30 mins- 1/1.5 hrs of power. Now they telling me I need to get my facts right and they have been very busy providing power to the ill and elderly. Bottomline I have lost in every way more than I gained using Electrosurgeon.