Why won't my partner respond?

me and my partner text over the phone a lot but i always notice ill send things and they won't ever respond and when i bring it up they said they had to do something. its quite confuseing because they never tell me they gtg and when i text them again to add to my first text they respond right away is there a reason for this. by the way on a side note ussually they just stop responding after random texts i send like hi i missed you. am i missing something or do they just not wanna talk to me... im confused on this.

Why won't my partner respond?
Post Opinion