C03 and C08 are related to an open closure in Hitachi's chart. C08 also includes checking for an overloaded drum; confirm whether your model indicates a front door or top lid.
The grouping appears in the official Hitachi Home Appliances FAQ. It does not show that both codes are present on all of its platforms.
Check the closure without adding pressure
Stop the machine and wait for movement to cease. When it can be opened, move away any garments crossing the edge and see whether an excessive load is preventing the lid or door from reaching its position. Adjust the amount to the program before closing it again.
Do not strike the latch or manipulate the lock with magnets or bridges. If it looks damaged or does not engage normally, stop trying to start it.
If the real problem is that the closed lid will not release, C09 requires a different interpretation. With persistent C03/C08 and the area clear, seek service and note whether the alarm appears before filling or during operation.
Specify which of the two codes appears and whether the load is pressing on the closure; avoid summarizing them as a broken door without checking.