Can't switch from Wifi to Mobile data automatically

[Dready]

(Samsung S9+)When i'm connected on Wifi everything works fine,but when i get out of range it switches to mobile data but no internet is available.I see that there is no ip address also.I have to swith to airplane mode on then off ,then the phone will conect on mobile data.Anyone else has or had this issue?It's annoying,i'm planning to return this phon if this issue is unsolvable.

[ascuteln]

No, I don't have dual sim and I use Bell Network in Canada

[Wai55]

Same here, S20+ on Bell

[pokerwork]

Had this problem and found this thread which has been very useful so thanks folks.  Recently moved from an old S4 to an A41 with Android 10 and got this problem i.e. when I leave the house and drop the wifi connection I don't automatically get data over mobile network.  My first fix was simply to restart the phone and this worked.  I then read this thread and particularly the note about APN authentication type.  The default setting on the Internet APN setup on my phone was PAP.  I setup a new connection and left it 'not set' and then switched to this connection and all is working OK.  I'm in the UK using BT/EE network.

[giddyup69]

I just posted something similar in the Note 20 Ultra forum.  Have this exact same problem in Canada on the Telus network.  Exact same issues others are pointing out.  It's an absolutely maddening issue for a flag ship phone.

[Dready]

Hi.Almost 3 years and no fix for this issue on my Galaxy 9+.Not sure what is causing this issue but it's quite annoying. As i see this issue still happens on newer models.Never got an answer from anyone.

No one knows if :

1.The sim card is causing the issue

2.The phone is not compatible with the network

3.Something is buggy and no one is fixing it.[ Without any updates installed the phone was working fine. After the first update everything got messed up.]

4. Motherboard Issue.[Got the motherboard changed twice....same issue! ]

[Sencer]

Hi, almost a year ago I renewed my simcard from my then operator and the problem fixed by itself. I did nothing else. Recently, I changed my operator so got a new simcard and never had this problem either.