Charging does not show the lightning symbol because it has not entered the charging state, you can try to use the following methods:
Clean the charging jack at the bottom of the phone, using a wooden toothpick or a small brush. Replace an available power adapter; Replace an available charging cable (data cable).
To avoid the problem of not being able to charge again in the future, please pay attention to the regular cleaning of the charging hole at the bottom of the mobile phone when you usually use it, because the mobile phone is usually installed in the bag or pocket for a long time will accumulate dust, too much dust will lead to poor contact, pay attention to heat dissipation when using the power adapter, do not cover the clothing on the adapter to use the power adapter. Try to avoid excessive bending when using the power cord.