I lost my phone and my giff gaff number in it. I bought my phone in the Carphone warehouse and I was paying an insurance for it. So they asked me to contact my network so they can put my number on the black list.
In the further information box write 'please provide my IMEI and confirmation of blocking to the insurers'. giffgaff will send this direct to your insurers. They will not send it to you as the insurers ask for this to be sent directly to them to reduce fraudulent claims. giffgaff will however send you a copy of the IMEI if you need it for a Lost Property 'proof of ownership' as example.
Stage 3 LOSS DATABASE
I would also suggest that you register your phone on the Immobilise website and then report it as lost. https://www.immobilise.com/ It's a national database and totally free of charge. You can use the website to report the loss or theft of your phone. The police can also use this database to return it to you if it is later recovered. Hope this helps.
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