i to have had a number of silent / dead calls from this number after i requested a quote online with More Than, (and yes i have had MORE THAN enough of the silent calls, i went to the ofcom site and found the below FAQ regarding silent calls. hope it helps explain why you are getting them.
. What are silent calls?
The term ‘silent call’ is a generic description for all those types of telephone call where the person called experiences silence on the line when they answer the telephone and has no means of establishing whether anyone is at the other end. There are a number of circumstances which give rise to silent calls.
"Most silent calls are not generated with malicious intent but are caused by automated calling systems such as predictive or power diallers used by call centres for telemarketing, market research, debt collection and other purposes.
The diallers are programmed to generate and attempt to connect calls. If there are not enough call centre agents available to handle a call it is abandoned if the call is answered by a live individual. These abandoned calls can cause annoyance, inconvenience or anxiety.
Another source of silent calls is where a fax is distributed to a voice phone line. If the person called answers such a call they are likely to hear the high-pitched tones of the fax ‘handshake’ protocol.
The most serious are silent calls made with a malicious intent to deliberately frighten or annoy the person called. In such cases, the caller may be guilty of a criminal offence under section 127 of the Communications Act 2003."
i will be sending a letter / email to watch dog if this continues and then ill also report them to ofcom.
good luck all