Weaning (21 month old)

I have been trying and TRRRRYING to pump to do the mix technique.. two electric pumps, and one manual later it's just not happening on my end. I have been offering other milk, but she straight up would rather flop over. She is lactose intolerant, so have tried all the alternative options (except for rice and oat because those have been unavailable in my area for a long time) also don't want to buy huge bulk online because if she doesn't like it, I'll be stuck with it.

Any suggestions on what to do? 😭 Thanks in advance.