Nasal congestion

Has anybody experienced nasal congestion in there LO, and if so, what helped? My LO is super congested, especially when she is laying flat. It doesn’t seem to bother her and she is nursing fine. I have used saline drops a couple times and it seems to work for a short period, but then sounds congested again. Her nose is clear, no boogies or anything so not sure what’s causing it.