Will not start now it is the immobilizer?

I do not have any access to specific information about your car, but I will try to help you troubleshoot it. To me, that does not sound like something that the immobilizer is doing. It sounds more like either (1) The battery is weak or cable connections are weak or (2) The starter itself is failing.

If you can do it and have the tools, you should start by checking your battery terminals. If you can move the cables where they are connected to the battery, then they are too loose. Simply tighten them up and see if that helps you.

If the cables are tight, find your starter and make sure the cables and bolts on it are very tight. Again, you should not be able to move the cables on that end.

Start with that and let us know what you find.

Hello,

When the immobilizer gets triggered, you will get a blinking car icon with an X over it, on the dash.
Most of the time the immobilizer gets activated due to a bad start control unit (SCU). The SCU is what controls the staring of these vehicles.
Try locking and unlocking the vehicle 5 times with the key fob. Unless there is an internal fault it should reset the antitheft and allow you to start the vehicle.

Keep in mind when the immobilizer gets activated, the vehicle will not crank over.

Please let me know what you have been experiencing or if you have any questions.
Thank you.

https://www.2carpros.com/articles/how-to-reset-a-security-system

All the proton have very similar setup as far as immobilizer is concern.

Another common way for any vehicle is to disconnect the battery and wait for about ten minutes, then connect it back and try to see it that resets it.
If these methods don't work then it is likely a faulty immobilizer module.

Have you tried to jump start it? It almost sounds like a weak battery.
When the battery is low on charge or faulty it will have just enough to crank over maybe once or twice. It can turn on the lights but not have enough power to start.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Can you tell me what else you have tried? Just one crank can be due to a weak starter drive or even a seized pulley.
Also, if it was the immobilizer, you would not get any crank. It would simply not make any noise.

Do you have the flashing security light illuminated on the dash?
Typically, the non-communicative transponder means the module itself is nonfunctional.
Since Proton is not sold in the USA I don't have access to the repair manual of how to access the transponder.

You might have to use a scanner that can communicate with the module and see what error codes there might be present within the immobilizer module. This could determine if this will need to be replaced. Now if you are not able to communicate with the module, even while using a proper scanner it could be a bad module as well.

Generally speaking, when there is no communication to the transponder it is either not getting power due to a bad wiring issue or the transponder itself is bad.
So, a good next step would be to check to see if you are getting power to the module. It should have 12V to the module.
As I mentioned before, since Proton is not sold in the USA, unfortunately I do not have access to the repair manual or diagnostics.

If you have power, then it could be a bad module.