Dunno if it's what happened in this case, but solar flares make the atmosphere bigger* which increases drag on satellites in low Earth orbit. That said, the sa

Dunno if it's what happened in this case, but solar flares make the atmosphere bigger* which increases drag on satellites in low Earth orbit. That said, the satellites have an expected life of 5 years so it's not necessarily a big deal. Their planned constellation is so large that it's dependent on having a nearly continuous churn of replacement satellites. * This is a bit of an oversimplification