Firstly the stock answer...
Pixellated pictures on live TV are often the sign of a signal fault. If you've rebooted your box once, then there's likely a fault somewhere, so this will need VM to intervene. You're likely to need either an engineer visit or a replacement box, depending on what VM's remote diagnostics turn up.
Second the personalised bit...
What did the engineer do on Monday? You need to follow the same process as first-time round - check for area faults (0800 5610061) and then report your fault to VM. You may need another engineer visit, there may be another fault that also needs a fix.
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