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Troubleshooting

eSIM too slow? FUP and network checks

3 min read · Updated September 13, 2026
If it suddenly got slow, the cause may be (1) exceeding the high-speed data cap (FUP) on an unlimited product, (2) being connected to a weak local network, or (3) a signal problem indoors or in a crowded area. Check your high-speed data cap and the network you're connected to, and if it's a multi-network product, try switching networks.

Check the high-speed data cap

Even on an unlimited product, speeds can slow once you exceed the high-speed data cap. If you've used a lot of data today, that's the likely cause. When the limit lifts varies by product, so check the product details (in some cases it doesn't reset on a daily basis). See the "The unlimited trap (FUP)" guide.

Try switching networks

If you're attached to a weak carrier network, it's slow in rural areas and indoors. Turn off automatic network selection and try manually picking a different local carrier (when it's a multi-network product). If 5G is unstable, locking to LTE is sometimes more stable.

Other checks

  • Turn Airplane Mode off for 10 seconds and back on / restart
  • Indoors, underground, and crowded tourist spots can be slow to begin with → move location
  • Check whether a VPN or a data-heavy background app is running

FAQ

It's unlimited — why did it slow down?
You've most likely exceeded the high-speed data cap. When the limit lifts varies by product, so check the product details (not every product resets the next day).
Will switching networks make it faster?
If it's a product that supports multiple networks, you can try a different supported network. But if the product's speed limit is already in effect, switching networks may not make it faster. Single-network products can't switch.
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