why does my phone have an annoying non deletable pop up?

[AC Question]

I have a Samsung S5 and have had it for about 2 years. Just over the last few months, everytime I select an app, I get a pop up from fee.tripnar.com and I just can't get rid of it!! Soooo frustrating! Can anyone help? I have tried to block it but am having no win!

 

[Tim1954]

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