For Europesure policies with policy numbers commencing LB200xxx
You should tell them You have a Europesure travel insurance policy and give them the Contract number and the certificate number shown on Your Schedule of Insurance
For Europesure policies with policy numbers commencing LB100xxx
When you call them, tell them you have a Europesure Policy and quote Scheme Reference A04943
You will also be asked for the Contract Reference and your certificate number, both of which can be found on your Schedule of Insurance