Hello Ayesha - Our requisition and cancellation procedures are set out in our
Practice Guide 50
We may reject an application where it is substantially defective and there is no prospect of us being able to proceed with it.
Where we have accepted the application and find there are gaps or issues that need to be addressed then our normal practice is to raise a requisition followed by a warning / reminder if the matter is still not resolved, and then cancel the application.
There could be some situations where the requisition may have not reached the solicitors because of email glitches, but most of the solicitors have access to our Portal / Business eServices and would be able to see the status and access all correspondence using the View Application service in there.
However, it depends on individual case. If you need to investigate what exactly happened in your case then you can contact our Customer Support using the Contact form - https://www.gov.uk/guidance/contact-hm-land-registry
I hope this helps.