'Engine too hot stop car' warning

Thanks in advance to anyone who can assist.
Purchased my 1.4 Pluriel Cote d'Azure soft top four months ago, has a full service and MOT prior to me picking up. Done 43000 miles and its a petrol manual.
6 weeks ago I started to get a warning light, 'Engine too hot, stop the car'

So first time it happened I had been driving in the rain to get my child to school. Waited for Recovery Co and by the time they got to me the fan had stopped running and cooled down. He checked engine, asked me if I had had my blowers on and were they running hot or cold. At first they were running cold and then he said that it may be a blockage in the pipe as coolant now contains antifreeze and can sometimes cause the car to overheat, the coolant was empty so he re-filled it using clear liquid and said if he squeezes the pipe and have blowers on this should cure it. The air coming out the blowers was getting warmer and he said this has done the trick and followed me home nice man.
A few weeks later I had just gone through a huge puddle and descended down a very steep hill when low and behold, same message. Cooled the car down, waited for hubby to arrive and drive the car back home. Coolant level completely gone. Re-filled, now yesterday having come down a very steep hill (no rain this time) warning light again. This time coolant rusty coloured and fan came on but engine didn't seem hot at all, in fact I'm not sure if the engine had overheated at all during these three occasions.
Car now sat on drive and I'm curious as to what anyone else thinks or maybe encountered with similar issues.
Thanks

Welcome to the forum cosmos69

from what you have described there are problems with your cooling system.
1. you have a leak
and
2. you coolant is old/contaminated

I know you have a leak because you stated on more than one occasion that

the coolant was empty so he re-filled it

and

Coolant level completely gone. Re-filled,

So you should get the leak found and fixed. If you keep driving it before its fixed, expect even more expensive problems.

The leak could be very small, on a hose, radiator, head gasket or water pump... or somewhere else


The second problem, neglect of the cooling system is from your description of the coolant

This time coolant rusty coloured

This indicates a lack of care. The coolant should be bright and red or pink.
Care is servicing and having the coolant drained and refilled with new stuff every so often.

You can find out about the correct type of coolant for your pluriel here - C3 coolant.