Hi @Nadia30 it's always tricky when you have a demanding guest, especially one that is already in your space. You are emphasizing the word "NEED" so I'm guessing the guest demanded, more than requested, this service.
I totally agree with @Helen3 that you simply say to the guest " here's a few more towels for your use during the stay, but I'm not able to provide you with hotel service". I didn't look at your profile so I'm not sure how long you've been hosting, but many experienced hosts have learned to be firm and clear with guests and not leave room for negotiation. Guests like this, like naughty 13 year olds, are masters at manipulating the situation, so it's up to you on how strict that you want to be.
If it were me, I'd give them a few more towels, tell them that's it, and say "I'll bring you additional towels next week, after I've done laundry". You want to be seen as accommodating, but to a point, not bending over backwards to give them what they want.
Good luck to you!