@Dottie0
I think it is something you should have discussed with the guest in advance - if you state you provide essentials then it is my opinion that this should be provided during the entire reservation period regardless of length of stay. If you provide a certain amount regardless of length of stay, then you should clearly explain that you only provide some basics to get them started but they need to buy their own after what you provide runs out.
I usually have guests staying for up to 4 months and I provide shampoo, conditioner, soap, TP for the entire stay. I also handle laundry of towels and bedding so I give guests a new, clean towels to last them a week and I provide bedding/sheet changes every 2 weeks. I also usually do a quick vacuum of the guest room floor and under the bed once a week. All of this is factored into my price.
Long-term guests need a different set of rules and expectations. You may want to have a quick chat with the guest, just be honest and nice about being new with long-term guests and so there should be some clarification about housekeeping and house rules in general. Talk about the guest's expectations as well as your own, and I'm sure you will be able to find a nice compromise. I had to go thru this with my first long-term guest as well and luckily, she was really nice and understanding that Henry and I were new hosts (she was also a 1st time Airbnb guest) and helped us set many of our ground rules.
Just my personal opinion, provide the TP and towels but tell her the shampoo/soap are provided only once at the begining and after it runs out, guests are expected to supply their own. Just appologize saying you are sorry this was not clearly covered in the listing description. (You could say you rarely get long term guests and all prior guests always supplied their own amenities so you must have forgotten to mention this.)
Good luck~!