Spicing up relationships?

So what do you guys do if the relationship is getting to dull? I don’t mean this in any bad form or intention to insult or offend anyone. Please I don’t mean it that way. Have had many of my posts get deleted 😂 but I mean if a relationship is becoming too “routine like” even the sex is the same. Maybe try that thing that never happens? *chandler voice* . I’m 20 okay guys, usually my relationships don’t last this long and I’m scared it’s getting boring 😭 this is my 2nd attempt at a relationship this long and the last one ended cause of this same reason! God it’s like a curse. So any tips ? I’m up to anything 🙄