To think this is rude?

[MiaMarshmallows]

When someone asks you on a number of occasions to help them with something by text. When you agree, they never reply to thank you or acknowledge it.
Aibu to think this is rude?

Have they seen the reply?

Yes. Showed up as 'read.'

Well when/ if they reply say sorry when I didn’t hear from you I assumed you didn’t need my help and I have plans now

It feel like common etiquette is ruined by our phones now! It's so easy to be rude, even I can be bad at replying my auntie etc. I bet they just got busy and forgot to reply. But good on your for helping people :)