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Tristia Harrison, chief executive of TalkTalk, says trading in the first half "is in line with our plan".
Revenue is up 1.3% to £387m and cost savings are on track.
TalkTalk has failed to improve its standing on customer complaints in Ofcom's annual survey - the broadband provider has come bottom of the table for the third year running.
Its customers were most likely to be unhappy with the outcome of complaints.
A spokeswoman for TalkTalk said the data showed an "improving trend" on the number of complaints.
There was some respite for Metro Bank on the stock market after heavy falls sparked by errors in the way it was accounting for some of lending.
The shares gained 10.4% - lifting off record lows reached on Thursday.
They ended around 1,200p - still well off the levels around 2,200p they had been trading at before the accounting issue emerged.
Talk Talk ended 4.7% lower after it told the stock market its full-year core income will fall short of analysts' expectations, and its own previous guidance, by between £10m and £15m.