Launch the PMDG Operations Center software if you have their 777 in your collection. A new Service Pack (about 130 Mb) will be downloaded to update the Worldliner 777-200LR.
And if you also have the expansion 777-300ER, another specific update of about 30 Mb is available. When they are installed, close and restart PMDG OC software to repair your liveries. You’re done !