Works incorrectly with liquids, with a positive request, the combinator displays a minus. For example, I set it as a provider and set 25000 oil, but oil -25000 is displayed. The station is invisible. In the LTN manager at the station, a negative request is not displayed, none is displayed at all. Before the last update everything worked. The same problem is with water.

Requests are never positive. A positive number means it is a provider (supply). The combinator will change your numbers to negative by default since a positive number will not work as a request. This can be changes with a setting so that you can enter positive numbers.

Check to make sure that your combinator has "Enable Requester" checked, and that your "Request Threshold" is less than the amount you are attempting to request. Note: The Stack Thresholds are ignored for fluids.

Just noticed you said you set it as a provider... You don't specify values for a provider, only requests. The supply available to provide (the positive number) comes from the containers that are holding the fluid, not the combinator. You only spcify requests (and control signals) with the combinator.