British driver Chris Ingram is understood to still be waiting for the €100,000 he was awarded for winning the 2017 FIA European Rally Championship Under 27 championship.
The prize money was a 'career development fund' centred around a pair of 2018 ERC outings.
By the end of the 2017 season, the ERC organisers stipulated those drives should be taken with Motorsport Italia.
Instead, the 24-year-old Manchester driver made a separate deal with Toksport - an agreement sanctioned by ERC.
With additional private backing, Ingram tackled five ERC rounds and two WRC events - including a WRC 2 debut podium in Turkey - with the German team in 2018.
A source told Autosport: "When Chris started the 2017 season, there was no mention of a Motorsport Italia deal - just the €100,000.
"He won the title and got the picture being handed a big cheque for €100,000.
"He keeps being told: 'The money's coming, it will be there...' but he still hasn't seen any of it and he's facing some very big bills now."
Ingram has declined to comment on the situation.
An ERC statement said: "There will be no comment on what is a legal matter."
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