If you are using a GSM SIM card or related chips, you may need to configure your device as required, you may need to contact your GSM provider. Go to Settings>More>Mobile networks>Access point names
select the APN you want to connect to and edit, press options, then save(If you think you have editted correctly)
If android, go into settings, mobile& networks and make sure you have "data" enabled. If your provider allows roaming free, or if you want to pay extra, check the data roaming box. Many companies provide it free. Check your cellular/data plan with your company.
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If you are using a GSM SIM card or related chips, you may need to configure your device as required, you may need to contact your GSM provider. Go to Settings>More>Mobile networks>Access point names
select the APN you want to connect to and edit,
press options, then save(If you think you have editted correctly)
then apply that APN
Hope this helps
If android, go into settings, mobile& networks and make sure you have "data" enabled. If your provider allows roaming free, or if you want to pay extra, check the data roaming box. Many companies provide it free. Check your cellular/data plan with your company.
Usually simply rebooting your phone, regardless of make and model, takes care of any connectivity issues.