Red Power light on Dlink router

[#1]

My DSL-2640B router has given me reliable and trouble-free service for 18 months. Now the power light is red instead of its normal reassuring green hue, I'm missing a few other lit indications, and I no longer have an internet connection.
Is the router in need of replacement, or will a factory reset bring it back to health?
In terms of a replacement, is the Thompson one currently supplied by Plusnet any good, and can I get one free if I commit to 12 months subscription?

[#2]

you can get one, you dont have to commit to any thing, your max contract length is 1 month, but if you leave before 1 year you pay for the router, after one year it is free

[#3]

Thanks Pierre for the clarification.
I think I will try a factory reset (Dlink recommend 3 or 4 times) whilst I try to work out how I go about ordering a replacement.
I put in a support ticket query which won't (apparently) be responded to (or even looked at) for at least 26 hours 
Tried phoning but wait time was over 10 mins and I'm at work, so shouldn't be using phone for this length of time to 0845 numbers.
I really hope I can get the Dlink up and running because it has been reliable and good at maintaining sync, and I don't know much about the PN supplied and pre-figured versions of the Thompson

[#4]

hopeful that one of the coms team will pick it up,  you can phone Sheffiel CSC on 0114 2965198

[#5]

Official response from Plusnet is that the router is faulty and cannot be fixed. Having tried numerous times last night to do a reset to factory settings, I'm inclined to agree.
Plusnet are sending out a replacement, but it will be a Thomson wireless. As I understand from the setup guide, this comes preconfigured and should be a simple 'plug in and play', with wireless set up and secured with a preconfigured network name and password. Can these settings be changed, and is it a good idea to do so, or is the default Plusnet configuration more secure?

[#6]

the security is OK WAP 2, you can change the code if you want to, the code is printed on the router base and is all caps, you can also change the log in to the router name and password if you want, do all changes while on Ethernet, if you then drop a clanger all is not lost

[#7]

Thanks again Pierre.
I might just keep the wireless password assigned, it'll probably upset the neighbours though