Post Covid spo2 level dropping.

My mother was tested positive for Covid on 23rd March with a Severity score of 16 .she was admitted in ICU where 6 dose of remedisivir and other antibiotics injections were given to her.She was discharged after 10 days when all her Reports came normal .she was Given steroid Medrol 16 mg -7 days (OD) Medrol 8 mg -7 days (OD) Medrol 4 mg - 7 days (OD). Doxycycline, Ivermectin,Asprin 75 and multivitamins and vitamins C So she was recovering very well and CRP was also Normal -2.30 But three days ago she started feeling heaviness around chest and her O2 level dropping when she is asleep Her 02 level is now at 93-94 but when she fell asleep it drops to 86-88 , Another CT scan was done and the severity score this time was - 7 , Now from last three days she is unable to sleep properly because of dropping Spo2 and No experience doctor is available in my city I don't know what to do and what Mediation are needed so that she can get relief from dropping O2 and chest pressure