Automatic transmission hold function not working

This will be an internal problem with the transmission, hard to say at this time if it will be electrical or mechanical. there may be a fault code in the transmission, not all codes will set a fault light. If no codes the problem probably will be mechanical, so first thing to do is see if there is a code and you can also get a check done with a factory scanner to see if the electrical solenoids are switching on and off.

Thank you for the reply. just a note to inform you that all the forward heard are working fine gear changes are spot on no abnormalities only that the parking mode is not happening. The scheduled AT fluid change was supposed to be at sixty kms but was delayed can this delay cause the error. would appreciate a reply.
Regards,
Patrick.

another note; no fault CODES on the factory scanner. absolutely no DOC.

Probably a mechanical problem with the park lock pawl in the transmission, this will not set a code, was park selected with the car moving forward or reverse even very slowly ?