
I mean the kingdom (or whatever society she's in) should have a limited amount of gold/silver/copper which they use for commerce. Those materials suddenly disappearing through her magic, rather than circulating through multiple business transactions, means they would have to mine more materials to replace the missing wealth.
The cycle of her earning money, destroying it with magic, and then earning more money to do so again would gradually exhaust the source of money. So it's not an immediate issue, but on a larger scale or over a long period of time, she could essentially bankrupt the kingdom. If the sources get exhausted enough, the kingdom could become desperate and perhaps declare a war in efforts to gain more access to mines to have more wealth.
Again, this is obviously a nitpicky and cynical detail that probably won't actually be an issue in the story, but I just found it amusing.

Ohhhhh
I get what you mean XD
Tho I don't think that's a big problem cause she's the only one using it...
And the kingdom is quite bigg
So the mines will also be big
They also trade with other countries so they can get money through that without starting a war or stuff XD
And it's not like she'll use all her money to buy stuff from the other dimension cause she'll need it in the world she's currently in...
Besidesss
She's in a magical world and no one knows how big that world is and how big the kingdoms territory is so the mines can go as deep as it can and there will be a lot of ores cause it's a different world XD
I think the kingdom she's in now is quite big so if they do have a problem with the source for copper and stuff they can just trade with the other kingdoms

I feel the same as well. For the story's sake we ignore some of the finer details, like logic, but so many times we want to point out that actions, no matter how benign they seem, have consequences. There are so many times I want to point out how a protagonist has ruined the economy such as by being the only provider for all goods in an area. I mean that would mean all those employees, those involved in production for all goods from agriculture to transportation to manufacturing would be out of a job and be unable to work to pay for said goods the mc now holds a monopoly over.
Similarly, of they have a game system that creates money but does not use money they would inflate the economy til it collapses (like a system that sells monster parts)
... but if she plans to continuously earn money to then spend on the summon from another world
that money disappears / is destroyed, and that could destroy the economy, especially since they aren't using paper money but actual gold/silver/copper pieces.
I know its just a minor detail, but it immediately came to my mind when she used the money and it disappeared