With f=900 mm and a 25 and 10 mm eyepieces you would be viewing at 36x and 72x.
36x is a very reasonable magnification under any condition, and 72x can probably still be considered "useful magnification" at least under good conditions.
I don't have particularly good eyesight but I can assure you that in my 8x42 binoculars (only 8x magnification, 42 mm aperture) I can resolve all four Galilean moons of Jupiter (if they're far enough away) and the two little bumps on the side of Saturn where its rings extend.
I last did this last summer when they were at opposition.
Now, here's some potential kickers; sometimes Galilean moons may be very hard to resolve because they are behind Jupiter, or in its shadow (eclipsed) or simply too close to Jupiter's bright disk (or occasionally eclipsing each other!)
And sometimes Saturn's rings are so close to edge-on that they are difficult to see.
If you have the date and time that you looked at Jupiter it should be pretty easy to find a website or ephemeris that shows how far the Galilean moons were from Jupiter to see if you just chose an unfortunate time to look.
But for Saturn you really really should have been able to clearly resolve those rings. Here is a set of simulated images of the planet at each time Saturn is at opposition, meaning that it's a bit closer than average and up most of the night. It shows the slowly rotating pattern varying with Saturn's orbital period of about 29.6 years; the last image is almost the same as the first image.
If you looked in 2022 with the instrument and eyepiece you describe, you certainly should have seen Saturn's rings.
This sequence of simulated views demonstrates the 29.5-year orbital period of Saturn by opposition date, as well as the dramatic changes in the orientation of the planet's ring disk. The ring system revolves around a fixed axis, so both sides of the ring disk are visible from Earth during each period in which Saturn orbits the Sun.
Reference: Meeus, Jean (1988) Astronomical Formulae for Calculators (4th ed.), Willmann-Bell
Source: Wikimedia Commons
This is an animation of the 28 images of Saturn shown in Saturnoppositions.jpg (simulated views using a computer program written by Tom Ruen). This animation demonstrates the 29.5-year orbital period of Saturn by opposition date, as well as the dramatic changes in the orientation of the planet's ring disk. The ring system revolves around a fixed axis, so both sides of the ring disk are visible from Earth during each period in which Saturn orbits the Sun.
(See source file for more info and references.)
Source: Wikimedia Commons