initially the B + capacitor (100uF / 450V and tny277 were burnt out. Replaced them and also the 470uF / 10V capacitor of the 12V line.
The TV comes to work but after a while the source is on and off. Note a heat generated by the source . Either it has another faulty component besides the main capacitor and the tny277 or some board is consuming current beyond normal.

Download the service manual and take measurements.

Download D26W931-D32W931-LC32W053-LC42H053 : D26W931-D32W931-LC32W053-LC42H053.pdf

I started by checking the components of the FAN7529 integrated primary stage when I found the 0 ohm resistor R920 open.
the resistor R920 was replaced and, while powering the source using a series lamp, the lamp started to flash (I even measured the voltage on capacitor C920 showing a little high voltage) until it came at a time when the lamp didn't light up.

After replacing the resistor and testing the source right away, I measured the voltages on the capacitor C920 when I realized that the voltage was back to around 185V again. It may be that the integrated FAN7529 has burned again

The voltage on pin 1 of the FAN7529 is around 1V and the voltage on capacitor C920 is 185V.

Check the voltage on 8 pin fan7529, if it is less than 11v, then change fan7529.

voltage ranging from 11.9 to 12v on pin 8 of fan7529