Late filing of ML

I need help. Nakunan ako, 4 months. Hindi pa po ako nakapag file for mat 1 kasi hindi ko po talaga alam kung paano and I had to rectify my UTI Kaya na bed rest ako for a week and after the next thing I knew, early labor na ko. Nalaman ko na pregnant ako nung 8 weeks na. Need a letter of explanation for due to non submission of mat1. I don't know kung paano gawin.