"Wast compatible" means "was not compatible." There are many synonyms for this phrase that can be used to convey the same meaning. Some of the possible alternatives are "didn't match," "weren't in sync," "were incompatible," "were mismatched," "were incongruent," "didn't fit," "were not harmonious," "were unsuitable," "were ill-suited," "didn't work together," "clashed," "had no agreement," "conflicted," "contradicted each other," "couldn't coexist," and so on. The choice of the synonym depends on the context and the tone of the communication, and the conveyed message should be clear and concise.