Catheter bag not filling

Hi, new to catheter day bag and husband is having problems as although there is urine in the line, it’s not flowing into the day bag this morning, any advice as to is this normal first thing in the morning if urine is thicker? He’s worried about it backing up into his bladder.
Any advice appreciated.

Unless your husband is not drinking enough, there is a clog somewhere in the system. It could be a blood clot or a hose kink. If it does not clear soon, he may need to go to urgent care.