Take for granted
American SlangDefinition
To assume something is certain or will always be there without question or appreciation; to undervalue someone or something.
Examples
"I used to take reliable Wi‑Fi for granted until a week-long outage showed me how much I depend on it."
"Don’t take your friends’ support for granted; say thank you and show up for them, too."
"He took her constant kindness for granted, and by the time he realized it, the relationship was already falling apart."