Urgent advice

[Benben2018]

Hello everyone,
Please i need an urgent advice, I'm an overstayer in the country and i put in for leave to remain in the country through my 11 month old son who is a british last november, While making the application i applied for a fee waiver as i couldn't get the money for the application then .
But i got a letter from the home office last week with the title
NOTIFICATION OF GRANT/VARIATION OF IMMIGRATION BAIL TO A PERSON DETAINED OR LIABLE TO BE DETAINED .
And the letter says further that i should go to Dallas court which is the nearest immigration center to mine to report on the 26th of march .

Moreover i got another letter after five days from the home office saying my application was invalid as i do not qualify for the fee waiver i requested for, that i should make a fresh application .

Please i really need an advice on what to do as regarding my issue,
as the letter says i mustn't fail to report at the stated (Dallas court) immigration centre
What could it be my faith if i go there to report
and whats the way forward in other to make a fresh application

Kinds regards
Benjamin