When an ECU chip upgrade appears to be faulty, the cause usually lies elsewhere. If your car has recently been for a service, it could be that there was a recommended upgrade of the manufacturer’s software. This could result in your chip having been overwritten, in which case it might need to be re written again. Usually the company that did the chip upgrade for you will rewrite it. They may even do it free of charge. If possible, ask them to update it to meet the current upgraded manufacturers latest specs. Other problems that might make it seem that the chip has lost power include other parts which might not be functioning properly, and the engine might need to be diagnostically checked.
For more info, see The ECU Chip Tuning Guide