Ok I did take the upstairs one and put it on downstairs and it worked so it's the wiring which is weird as I have it the same as down stairs. Is there a way to tell the correct wiring as I took these pics.

What is the brand and model of the device to which the thermostat wires are attached?

Sensi is the brand

Not the thermostat brand and model, the HVAC unit you're connecting it to.

It appears that the BA16 is the outdoor unit. As shown in the installation instructions figure 2, five thermostat wires are connected to the indoor unit.

Ok so does this picture help with the wiring . As its the blower in the attic that does not come on since I swapped it out. It worked right before but I unfortunately didn't take a pic of the wires on the old thermostat. I reset the switch and made sure the cabinet was closed correctly on the blower.

"Ok so does this picture help with the wiring?"

You've posted this photo three times. It doesn't point out any thermostat wires or, most importantly, show where they connect to the HVAC unit.

Sorry didn't know is there any direction where I find how they are connected by

You have to find the cable that contains the thermostat wires, find where the cable enters the HVAC unit, and see how the five wires are connected to terminals inside the HVAC unit.

Ok will try

Does this help the cause

Those aren't thermostat wires.

Did you take a picture of the wiring of the old upstairs thermostat? Sometimes the color of the wires does not follow the normal conventions (ex: W uses a blue wire instead of white). If you don't have the picture, then you have to trace it back the control board in the furnace to establish the wire colors and connection points.

Your 1st photo, the device with labels Fan, C, and Herm (for "hermetic" - means compressor) is a capacitor. Thermostat wires do not connect to a capacitor. Capacitors store an electric charge and provide a momentary voltage boost to get a motor (fan or compressor) started and/or a boost to help keep it running. Your thermostat would get fried, it runs on low 24v power, not the higher voltage of a capacitor.

The 2nd photo, device with 21, 23, 11, 23 is a contactor. It's a magnetic coil switch that engages to connect 120v or 240v power to the compressor/fan or to the heat when it needs to run. The yellow/blue and brown/yellow wires connected to spade terminals at the sides are 24v wires to engage the magnetic coil, coming either from the thermostat or from a control board in the air handler. The larger wires attached with screws are the 120v or 240v power wires.

As stated above, thermostat wire colors don't always match the expected colors per the labels on the thermostat. Or the colors may match the labels at one end (either at the thermostat or at the air handler) but not at the other end if the installers spliced on an extra length of wiring.

@mike_home: "Did you take a picture of the wiring of the old upstairs thermostat?"

He explained in his initial question that he didn't do that. He doesn't seem to be able to find the cable that contains the five thermostat wires that you and I have told him he needs to do.

Thank you for everyone's support after getting frustrated I started over on my steps. I opened the blower and did the blinking yellow steps and it was 24 again. The 3amp fuse that I changed from the start was blown again. I assume wires were touching when I turned it back on.i since changed the 3amp fuse again and we are working. Thanks for all the learnings and I appreciate all your time.

I didn't see the sentence about not taking a picture. Sorry for repeating that.

There are two basic rules when replacing an old thermostat. First rule is to shut off the power to the equipment. The second rule is to take a picture of the wires and their respective connections.