Error code 13 when trying to start Sap using cron

On a Red-hat 7.2 server we have attempted to automatically have Sap started by using a command through crontab, however we get an error and it fails.Running the "su nfdadm -c startsab" outputs the error below.

[root@TCT3VDE01 nfdadm]# su nfdadm -c startsap Checking syb Database

Database is not available via R3trans

-------------------------------------------

Error: starting database failed.

startdb DB start failed

check startdb logfile in home directory of user sybnfd

/usr/sap/NFD/SYS/exe/run/startdb: Terminating with error code 13

DB startup failed

If i manually run it by doing "su nfdadm" and after it the "startsap" command, then the server starts up normally with the following output.

[root@TCT3VDE01 nfdadm]# su nfdadm

TCT3VDE01:nfdadm 51> startsap

Checking syb Database

Database is not available via R3trans

-------------------------------------------

startdb completed successfully

Starting Startup Agent sapstartsrv

OK

Instance Service on host TCT3VDE01 started

-------------------------------------------

starting SAP Instance ASCS01

Startup-Log is written to /home/nfdadm/startsap_ASCS01.log

-------------------------------------------

/usr/sap/NFD/ASCS01/exe/sapcontrol -prot NI_HTTP -nr 01 -function Start

Instance on host TCT3VDE01 started

Starting Startup Agent sapstartsrv

OK

Instance Service on host TCT3VDE01 started

-------------------------------------------

starting SAP Instance DVEBMGS00

Startup-Log is written to /home/nfdadm/startsap_DVEBMGS00.log

-------------------------------------------

/usr/sap/NFD/DVEBMGS00/exe/sapcontrol -prot NI_HTTP -nr 00 -function Start

Instance on host TCT3VDE01 started

We have been trying to find a solution to this error, and so far our search has turned up empty considering that the error is specifically with the "su nfdadm -c startsap".

Is anyone able to assist me on this matter? If so that would be a tremendous help!