No access to recovery mode on Nokia C300 (opens in new tab)

I changed my lock screen pin but when I tried to sign in it said invalid pin\. Tried to access recovery mode but I can only get to Fastboot I contacted my carrier but they were of no help I have tried everything from soft reset to PUK\. still no success\. The manufacturer of the phone HMD is telling me to send the phone to them for repair however there is nothing wrong with the phone as evidenced by the carrier providing me with several fix it tips\. This is only an issue with the US version\...