Insurance claim

Vodacom insurance are the worst, i have handed in my phone for a claim. They declined the claim saying that i have used a different sim in the device, which is not the case, the repair shop stated that they can not recover any data of the device as the motherboard are damaged from the water (water damage) how can they then recover any data stating if used a different sim. Saying that i used the sim in 2019 on the day i received the phone. They are lying about this so that they don't have to pay for a new device.