@pert: Thank you for the suggestion. I'll try this one as soon as possible and will post the results.
@sterretje: We apologize if the way we're writing to the EEPROM is wrong, we just started with Arduino programming a couple of days ago so go easy on us hahaha! 
Anyways, we also thought that that might be the issue and that we still need to convert the string into individual bytes to be written into the EEPROM, but then if that really was the issue, then the above function "eepromtoUser()" wouldn't work right? The function was still able to read from the EEPROM and construct the "Ucontent" string via the "concat" command. We also tried putting that function into void loop() with a delay and it would repeatedly print the saved content in the EEPROM, which indicates that the data is indeed stored in the EEPROM. However, the same cannot be said if the power is turned off and on. 
But we'll still put your question into consideration and we'll try to convert the string into bytes. Do you have a suggestion on how to execute this? Thank you so much! ;D