UBI is implemented tomorrow. Every citizen gets $1000 per month.
Landlord now knows you have an extra $1000 that you never had before. Why wouldn’t the landlord raise prices?
Now you have an extra $1000 a month and instead of eating rice and beans for a few meals you go out to a restaurant. The restaurant owners know everyone is eating out more so why not raise prices and maximize shareholder profit as always. The restaurant/corporation is on TV saying, “well, demand increased and it is a simple Economic principle that prices had to increase. There’s nothing we can do about it”.
Your state/country has toll roads. The state needs money for its deficit. UBI is implemented and the state/country sees it as the perfect time to incrementally raise toll prices.
Next thing you know UBI is effectively gone because everything costs more and billionaires keep hitting higher and higher all time net worth records.
I guess the idea of UBI needs to be massaged a bit. For example, maybe it doesn’t go to all citizens, just to the households making <60k per year. Demand for services increases, but not in a way that services can indiscriminately increase pricing across the board. Not a full solution but solves one element of the proposed problem
The US already has that, in the form of various welfare programs (section 8 housing, SNAP food assistance, Medicaid, etc), although the earnings cap on those tend to be well below 60k.
Admittedly the number was arbitrary - I was just trying to address the major issue I saw in OP’s comment, not even as applied to any country in particular (I’m Canadian).
If you give everybody money, demand will not increase across the board. Demand of necessary products will go up while demand for luxury goods will go down, as those in more need will be doing a higher proportion of the spending than before. This will allocate more resources to necessary services instead of luxury goods. This won’t increase pricing indiscriminately across the board–it probably won’t even increase prices at all if the financing comes from taxes or some other “real” source.