Are you using 4G 21Mbps plan? Better upgrade to full speed plan (4.5G or 5G).
ps.
Last year I've upgraded from 4G 21Mbps to 5G (user can downgrade to 4.5G full speed). As 5G drains the battery much faster, I mostly using 4.5G and the difference is huge (comparing to 4G 21Mbps).