UNHAPPY

I AM NOT HAPPY ABOUT THE PAYJUSTNOW APP ALWAYS AFTER MY LAST PAYMENT, WHEN I WANT TO LONG IN ANYTIME OR WANTING TO GO TO THE SHOP AND BUY USING PAYJUSTNOW, IT SAYS PASSWORD/EMAIL WRONG SO I REALLY DONT UNDERSTAND AND I AM NOT HAPPY BECOUSE I AM A LOYAL CUSTOMER. I WANT TO BUY SOMETHING AGAIN BUT THE APP IT KEEPS ON DISSAPOINTING ME .