If that has snapped off inside the tap then you might need a new tap ?
If it is not snapped then you can replace both hot and cold heads for less than £15.
Look at bath tap replacement heads online.
They're at itI - In a monobloc tap maybe as in some cases there can be mixing before the valves but not in that bog standard deck mixer.
Get someone else, could even be a handy man to do that but given what they've done to the feeds then a local independent should sort it in jig time and I would hope, a lot cheaper.
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