With an issue date of 20th January, you had until 8th February to submit an Acknowledgement of Service (AoS) which would have extended your defence submission deadline to 4pm on Monday 24th February. However if you have not submitted an AoS, your deadline for filing your defence was 4pm on Monday 10th February.
So, did you submit an AoS? If not, you are very likely already the recipient of a CCJ by default. Check your MCOL history. If they haven'y yet realised, you need to get a defence, any defence, submitted right now... this minute.
So, DO we spend any time assisting you with a defence or is it too late?