4g data connection problems

[MRB11]

Since Marshmallow updated security patch my phone keeps dropping data signal for no reason.
Tried sim in another phone works perfectly.
New phone Z5 on Marshmallow.
Old phone Z2 on lollipop.
No problems on Z5 before security update

[Uliwooly]

@MRB11

Redownload the APN settings and also test it in >>> safe mode

[bestmi52]

Thanks tried both already neither seem to work.
Taken sim our cleaned it....still problem exsits.
Having to use my Z2 for now no problems with lollipop
Seems to be Z5 running Marshmallow.
Also drops WiFi signal as well since Marshmallow update.
Will contact Sony see if they know what is causing the problem

[Uliwooly]

@bestmi52

you might want to get a brand new SIM card, to narrow down the issue. 

Btw is your phone compatible with your carrier's LTE bands?

[bestmi52]

Yes after contacting BT mobile it seems there is a problem with the sim card.
So many thanks for your help

[bestmi52]

Yes it's an unlocked (sim free Z5) UK.
Purchased directly from Sony Web store.
As far as I know all LTE bands are supported that are used in UK on all networks.
Apparently BT mobile are having problems will all nano Sims that were given out over the last few months.
But did not seem to want to take responsibility for them saying there was no problems at there side..
So kept telling me it was the software update on my phone.
Typical BT If you ask me.
Anyhow looks like we have got to the bottom if the problem finally and it is currently being sorted out.