Answereda year ago

What does the "invalid alphabet pattern" error on TDAC mean specifically regarding passport numbers?

TDAC passport number issues invalid alphabet pattern visa application errors COVID Sandcastle visa input errors

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Rex ******

asked May 3, 2025

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Anyone else had "invalid alphabet pattern" on their TDAC in passport number?

Answer summary

Users are encountering "invalid alphabet pattern" errors while entering their passport numbers on the TDAC application. Common causes for this error include accidental spaces before or after the passport number and confusion between the letter 'O' and the number '0'. One user mentioned resolving a similar issue by deleting a trailing space when applying for the COVID Sandcastle visa. It's noted that separating letters and numbers with spaces can also lead to this error.

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Wannikea *********

An errant space before or after the number/data will generate this error.

a year ago

David ******

When I was applying for my covid Sandcastle visa on line i had a similar issue it turned out I was getting a space after I input passport no. Eventually all it took was a back space to clear the problem.

a year ago

Roger *********

@David *****

I remember coming during the Sandbox. I am afraid we didn't get to play with Sandcastles during that visit. :)

a year ago

Thomas *********

You use a „0“ Zero or the Letter „O“?

a year ago

Riccardo *******

if you put the space to separate the letters from the numbers, it could be the problem

a year ago

Roger *********

I vaguely remember something like that. A space at the end of your passport number?

a year ago

Bobby **********

Example please???

a year ago

Tod *********

What does that actually mean?

I tried to enter letters and numbers and it let me click over to the second page no problem

a year ago

Peter **********

@Tod ********

not a mandatorg field is it?

a year ago

Tod *********

@Peter *********

right but I don't know what they're asking. I tried my passport from the US which starts with an A followed by 8 numbers and it took it fine, then I went back and tried a passport of all alpha keys and it took that too (or let me progress to the second page)

a year ago