Along the lines of what @M.Herzkamp said on their answer, the robots don't communicate with Earth directly.
This was also a theme in The Martian. Communicating with Earth requires a powerful transmitter and receiver, so it is easier to have one large device built just for that purpose and give the robots equipment just strong enough to communicate with that device. If the transmitter is broken, the robots do not have equipment strong enough to reach Earth. Breaking the communication is easy. Debris from a sandstorm could have destroyed it, the sand could have buried it, or some other accident could have taken it offline.
You also need a reason why the robots would not fix it.
- They don't know it's broken
- They just haven't received any new instructions.
- They don't care because fixing it is not a priority.
- They don't have the tools to fix it.
- They were not programmed to be able to fix it.
As for why progress would be unmonitored- first of all, progress was mainly reported via communications. Second, satellites cannot see the progress because of the atmosphere. Part of colonization is giving the planet an atmosphere to maintain heat, keep water in liquid form, and allow plants and animals to live on the surface. Because it is so vital to other operations, the atmosphere would have been priority one. Melting frozen carbon dioxide at the poles is a common idea. It causes runaway climate change as the heat melts more CO2 which retains more heat. That atmosphere will block satellite imagery somewhat, like how Earth's atmosphere makes it hard to see the stars.
Another method for blocking satellites is burning fossil fuels. No one lives on the surface yet, so burning coal if it exists on the planet (maybe not because Mars is not know to have had the lifeforms required for coal) will provide CO2, coal dust that blocks satellite imagery, and the dust will be a good fertilizer for plants. Again, fossil fuels require a handwave.
The best way of hiding your civilization is to put it below ground. Maybe underground is more hospitable for the robots. Building in a crater would require less materials than building upwards because the hole has already been dug for you. From there, the buildings can expand underground like an ant colony.
If the robots want to end contact or are programmed to, hiding their progress becomes infinitely easier. Missiles or EMPs can take out the satellites and then you would have a reason for taking out the communication device.
The two things you really need to focus on are why the main communication goes offline permanently and why the satellites can't report progress. Hopefully some of these explanations are helpful.