4G not active on Sim slot 1

[Tauseef786]

I am on stock MIUI 12 ROM right now and it is all working fine except that my 4G/LTE isnt working in Sim Slot 1 anymore. it is only connecting to HSPAP.
I then tried putting the SIM Card in my mothers phone to check if i could get a 4G signal there and it immediately did, so i am certain its either a problem with my Redmi 8.

Strange thing as well is that i tried putting the SIM in the second slot of my phone and somehow it does get 4G/LTE connection when i have it in slot 2.

I already checked if the APN settings. Anyone else having this problem, because i couldnt really find anyone else with a similar problem.
Im afraid my 1st SIM Slot just got broken somehow
Can anyone help me fix this?

 

[LinhBT]

I am on stock MIUI 12 ROM right now and it is all working fine except that my 4G/LTE isnt working in Sim Slot 1 anymore. it is only connecting to HSPAP.
I then tried putting the SIM Card in my mothers phone to check if i could get a 4G signal there and it immediately did, so i am certain its either a problem with my Redmi 8.

Strange thing as well is that i tried putting the SIM in the second slot of my phone and somehow it does get 4G/LTE connection when i have it in slot 2.

I already checked if the APN settings. Anyone else having this problem, because i couldnt really find anyone else with a similar problem.
Im afraid my 1st SIM Slot just got broken somehow
Can anyone help me fix this?

Due to my understanding, on some Xiaomeme devices, 4G/LTE only active on 1 SIM slot ( 1 or 2 depends ). It may miss-understanding with the Dual stand-by which show the ability of giving both SIM slots to be active at the same time.

 

[Tauseef786]

Due to my understanding, on some Xiaomeme devices, 4G/LTE only active on 1 SIM slot ( 1 or 2 depends ). It may miss-understanding with the Dual stand-by which show the ability of giving both SIM slots to be active at the same time.

My mobile support dual 4G that allow 4G connectivity on both Sim slots. I have been using 4G on both SIMs before.

 

[LinhBT]

My mobile support dual 4G that allow 4G connectivity on both Sim slots. I have been using 4G on both SIMs before.

Then u may try Reset network settings, sometimes it helps

 

[Tauseef786]

Then u may try Reset network settings, sometimes it helps

I try this and also i flash a new ROM but problem not solved