My 1000W PC keeps shutting down during power outages. Should I buy a UPS or another inverter?

Hi guys, my PC has a 1000W Corsair Gold power supply with an RTX 3090 and an i9 14K. I tried using a Microtek 2350VA pure sine wave 24V inverter, but it keeps shutting down during power cuts. I don’t know why. Should I buy a UPS or consider something else?

Before this inverter, I had a Microtek 850EB, which had an overload issue, so I upgraded to the 2350VA inverter, but the problem remained the same. There’s no overload either, so I’m not sure what to do. I live in Delhi, so power backup isn’t generally an issue. Please suggest a solution.

Edit :- Ups - Cyberpower 2200VA, idk my Inverter has a UPS mode I returned It because it doesn't work. Damn I miss the ups mode if this model exists. But the shop guy said he enabled the UPS mode in it. ?