Vumatel installed, but... flashing blue power light and no helpdesk response for days

[MostlySatisfied]

So the installation team put my fibre line in, during which they managed to break the cable (which the second technician who showed up an hour or so later said is fairly common). He did a splice by the CPE and also outside by the main external box, which he seemed to think had resolved the issue. He seemed satisfied that the FX light was now solid orance (well, flickering a little but mostly solid). He told me the blue power light would stay lit "by the end of the business day". That was two days ago. I logged a ticket with Vuma support and I'm meant to expect a tech to phone to make a time but I don't expect this to happen now that it's the weekend.

So I'd like to ask what the reasons might be for the blue light to be flashing when the FX light is lit?

Thanks in advance!