The Lumia range are now obsolete so your best chance of repair would be a local phone shop or market stall, however, it probably isn't worth it.
You can put your SIM in any phone to use your credit and carry on as normal but if your new phone needs a different size SIM, any O2 shop will swap it for free.
Your photos etc will not transfer over though, so you will need to back them up to your PC or laptop.
If you choose to try a hard reset, all your content will be restored to the phone when you login again with your windows ID.
What MI5 said is correct the Microsoft Lumia phones are obsolete. Microsoft are not updating
so they are bascially insecure now too. I had a Microsoft Lumia 640 good little phone but had
to change it. I changed it for a Samsung Galaxy A70 at the Samsung Shop who gave me a trade in
for it! Really pleased with that.
It is not worth repairing really not putting good money into an obsolete phone.
Good you can use your sim anyway.
I hope you can find a nice phone to replace the Lumia
Good luck and welcome to the o2 Community Forum.
If I put a new sim card on my lumia 550, would I get signal so I can send and receive texts, use wifi and receive sound when calling and receving calls?
As my wifi isn't working, I can't send saved photos to my email, so can only take picture from my new phone to the pictures of my lumia 550
Would I keep the old text messages if I put my lumia 550 sim card to my new phone?
The text messages are not on the sim, so no, they will not transfer across to another phone.
You need to connect your phone to your PC with a data cable to back it all up.
From what you say, I don't believe a new sim will fix the problems with your 550 either.
I think that's a lost cause.
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