The 1366x768 firmware for T.VST59.031 is stable and widely used for repairing or repurposing older laptop screens and small LCD monitors. Success depends entirely on matching resolution, LVDS bit depth, and mapping format (VESA vs JEIDA). Always back up the original SPI flash before attempting any firmware change.
You flashed a file named "T.vst59.031 firmware 1366x768". Now the panel behaves strangely. Here is the debugging guide. T.vst59.031 Firmware 1366x768