I haven't run this through a screen reader, but it could be thrown off by your  .   needs to be closed with a semi-colon. Like this: . Also, there is no alt attribute for table. Provide an explanation, useful for screen readers, with the summary attribute instead.
On top of that, I would advise that you remove that empty cell and make a bigger space with CSS.
1 - Remove the blank row and provide a gap with CSS, like this:
HTML
| Account Number: |
1111 1111 1111 |
Reference Number: |
XXXX XXXX XXXX |
CSS
th { padding: 0 10px; }
2 - ...and on top of that, maybe it's a bit picky, so you could try:
| Account Number Heading |
Account Number |
Reference Number Heading |
Reference Number |
| Account Number: |
1111 1111 1111 |
Reference Number: |
XXXX XXXX XXXX |
CSS
thead { display: none; }
th { padding: 0 10px; }
3 - ...but ideally the table would be just like this:
| Account Number |
Reference Number |
| 1111 1111 1111 |
XXXX XXXX XXXX |
CSS
th { padding: 0 10px; }