sentence: other codes in reserve for this use : 522 ( had been used for mexico roaming ) , 588 ( as with 522 , '' easily recognizable '' codes as the second and third digit match ) , plus these '' regular '' 5xx codes : 521 , 523 , 524 , 525 , 526 , 527 , 528 , 529 ( other 52x codes for mexico roaming ) , 532 , 535 , 538 , 542 , 543 , 545 , 546 , 547 , 549 , 550 , 552 , 553 , 554 , 556 , 558 , 569 , 578 , and 589 .