heroku application error

[eslam2010011]

When I upload a large 5mb file this bug occurs. Is there a solution to this? Thank you.

sock=backend at=error code=H18 desc="Request Interrupted" method=POST
path="/doc/write" host=beta.nerodesk.com
request_id=1c4ce399-2ea7-4ac0-a8c3-579c038aaf67 fwd="50.201.186.106"
dyno=web.1 connect=1ms service=428ms status=503 bytes=473