Samsung S4 - 4G LTE not working

I have a 9505 S4 on 4.4.2 , and LTE SIM card. After I put the sim card in the phone, it shows LTE network in the info tab about networks for about a minute, but then disappears.

Later I only have UMTS and lower.
I tried with *#*#4636#*#*, but it doesn't show anything, it's not working.
Is it my phone?

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