Image caption Rebecca Fairclough says she has yet to be called upon despite signing up to volunteer

When the NHS invited people to become "volunteer responders" a month ago, there was a deluge of applications.

Three quarters of a million people signed up to help with jobs including patient transportation and grocery delivery.

Six hundred thousand were accepted on to the scheme, but so far only 50,000 tasks have been completed.

There's frustration from volunteers who haven't been used yet.

Rebecca Fairclough, from Manchester, applied to become a "check in and chat" volunteer - giving phone support to people who feel isolated.

But although she has spent many hours on standby, she is yet to be called upon.

"I've been on the app and marked myself as on duty, mainly in the evenings and weekends. So there's a total of 75 hours I've been online ready to volunteer and either make or take calls and I've heard nothing," she says.

Vulnerable people who are eligible to claim support from the scheme have also complained of it being difficult to access.

Among them are Rebecca's parents Joanna and Peter who are shielding at their home more than an hour away from her.

Peter has a lung disease which entitles him to claim support from the NHS Volunteer Responder scheme. But his wife Joanna says they weren't aware of it.

"In the shielding letter it tells you to get friends and family to collect prescriptions, and that's from the government," she says.

The couple say the first three weeks of lockdown were especially difficult for them, but they are no longer in need of extra support because their local village support scheme has helped them.

Away from the main NHS scheme, many smaller scale volunteer schemes have sprung up.

Image caption Volunteers are going door-to-door in Liverpool offering help to vulnerable people

In Liverpool, the St Michael's Community Support Network got under way quickly. It has been going door-to-door to check on people.

Organiser Kal Ross said: "We are doing a lot of courtesy calls to keep people company things like that, we've started to deliver hot meals.

"Really anything we can put our mind to, because the experience within our community is quite significant and if you organise that it can be quite a powerful thing."

The NHS Volunteer Responder Scheme is co-ordinated by the Royal Voluntary Service (RVS).

The organisers have apologised to volunteers who are still waiting to help, explaining that the system has taken longer to set up than expected.

They have also set up a new helpline to allow people to request help directly.

Rebecca Kennelly, the director of volunteering at the RVS, said: "I think the key is that we give everybody the opportunity to get themselves into the system.

"Anybody who feels that they are at risk or vulnerable, who feels that they can get support from a shopping role or prescription pick ups, or maybe a phonecall, please do give us a ring."

The RVS is encouraging those eligible for support to visit its website or phone the hotline which is 0808 196 3646.