1. use hashcat 3.40 (or higher, beta: https://hashcat.net/beta/)
2. use hccapx files (convert your caps with cap2hccapx from hashcat-utils or the converter: https://hashcat.net/cap2hccapx/
3. use some more intelligent attack, not brute-force, maybe dict attack? (mask attack would be like hashcat -w 4 -m 2500 -a 3 -1 ?u?d hccapxfile.hccapx ?1?1?1?1?1?1?1?1?1?1?1?1?1?1?1?1 , but the keyspace is not feasible!)
4. understand that length 16 is very, very, very long! Too long for brute-force! And it wouldn't just "take months", it would take thousands of years even if you would have the best and largest amount of hardware
2. use hccapx files (convert your caps with cap2hccapx from hashcat-utils or the converter: https://hashcat.net/cap2hccapx/
3. use some more intelligent attack, not brute-force, maybe dict attack? (mask attack would be like hashcat -w 4 -m 2500 -a 3 -1 ?u?d hccapxfile.hccapx ?1?1?1?1?1?1?1?1?1?1?1?1?1?1?1?1 , but the keyspace is not feasible!)
4. understand that length 16 is very, very, very long! Too long for brute-force! And it wouldn't just "take months", it would take thousands of years even if you would have the best and largest amount of hardware