If audiotapes get wet, remove them from the water immediately. Remove from the outer containers, but don't try to open the cassette casing. Let the tapes dry naturally. There's a chance that the tape will be usable when dry, but it may be prudent to replace water-damaged cassettes, rather than damage your equipment. If a tape breaks or will not re-spool, contact the supplier.
Some companies have replacement policies.
If a tape gets stuck or will not turn over, remove it from the tape deck and rap against the palm of your hand. Reinsert in the tape deck. This should clear up the trouble. It's probably time to clean your tape heads. When the tape crinkles and you're faced with an accordion of magnetic tape, carefully rewind the tape on the spools, making sure not to twist the tape.