+Motorola Mobility @motorolaUK refusing to repair my watch - need advise on what I should do

Originally shared on the community, but thought I would share it publicly. Not sure what I can do. Been having trouble with the repair centre and this was the third time I had to send it in during a 2 month period... frustrating!!!
Need advise - +Motorola Mobility refusing to repair my watch due to water damage

Been having problems with the repair centre and my watch. I have sent the watch 3 times to the repair centre to get it repaired. The first time was in end of June, second time in August and third time in August again.

The first reason was due to the watch not charging. Motorola fixed it under warranty, but the problem happened again within 6 weeks. Motorola then fixed it again under warranty and when they sent it back they sent it with a defect where tilt to wake did not work. I reported this new defect to them the day after I received the watch and sent the watch back to them as soon as they sent me a pre-paid postage.

Now they say that the watch is broken due to water damage. You can see in the picture where it is. They are saying that it will be too much to repair it. I ask them the price, they said over £200 to repair... 

I asked them how can the device be damaged due to water if the device is rated IP67 and it is obvious from the screenshot that the watch was never submerged in water for a long period of time. Also it was confirmed by them no crack was on the device.

Prior to this I have reported that I did not trust the repair centre because every time I sent it back it, I ended up sending it back in again and I demanded a full replacement. I will send a complaint letter to them but anyone got any advise on what I can do.
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