Commending him for his dedication to enriching the Byker community and young people in particular through more than 300 hours of volunteer work, Longstaff told Dale: "You're not just an inspiration to me, but so many others."
The 21-year-old midfielder added: "I just want to say a massive thank you from everyone at Newcastle United for all the hard work you've done for the Foundation and for Byker too.
"It's great that you're a volunteer on the Local Heroes matchday initiative - it means a lot and the help goes a long way and you're obviously doing great work at Byker Primary School which makes a huge difference.
"I hope you're really proud of yourself, Dale. Well done and thank you from all of us."
Dale, from Byker, Newcastle was thrilled with the message of appreciation from his hero and said: "I can't believe it! It's absolutely class to have that message from Matty and it really makes me happy to see it.
"I love volunteering and helping out with the Foundation - it means everyone in the community can get out, have fun and enjoy themselves with sport and other educational activities too. It makes such a difference for so many people and that's what matters to me."
Longstaff is the Foundation's newest Ambassador and was inspired, like his brother Sean, to support the charity after seeing the Foundation's work with James Geddes, a next-door-neighbour of the Longstaff family in North Shields who was diagnosed with Leukaemia as a teenager.
With support from the charity through its wellbeing work in the Great North Children's Hospital and employability programmes based at St. James' Park, James regained his confidence and built lasting friendships with charity staff.
Both Longstaff brochures have used their Ambassadorial roles to promote the work of the Foundation and its aims of motivating and mentoring individuals to achieve their potential.
Dan Hancock, a Project Coordinator at Newcastle United Foundation who has mentored Dale for several years, said: "We are all incredibly proud of Dale and the progress he's made personally through his time working with our teams at the Foundation and through his volunteering work.
"Dale has given his time to volunteer across a number of Foundation projects over the last ten years - his hard work means so many young people in Byker and particularly in Byker Primary School have been able to learn, play and make friends because of his time volunteering with us.
"He's overcome a number of different issues to get to where he is and his confidence has grown so much. We're proud to continue supporting him through our Employability programme and ensuring he reaches his potential."
Dales is one of hundreds of Byker residents of all ages supported by a long-running partnership between Newcastle United Foundation and the Byker Community Trust, part of Karbon Homes.
The two charities forged the United Byker initiative several years ago and have been providing a number of unique opportunities for the community ever since - from employability support, to activity in schools, extra-curricular programmes and health and wellbeing events.
Michelle Bell, Assistant Director, Byker Community Trust, said; "This is wonderful news and recognises the impact and role Dale has in our community by working alongside key partners.
"By volunteering, he has given so much back to the local community, which has helped a lot of young people to engage in activities and sports to help them keep active and fit.
"Well done Dale, you are a true inspiration and I am glad you received a personal message from Matty in recognition of the role you play in Byker."
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