After integrated with cHar server, cHar extension might not be able to establish any calls, in the trace you might encounter similar error report below from asterisk, this article provides patch to fix this issue.
/ysdisk/ysapps/charhotel/agi-bin/CHAR/checking/checkinout311.php: Failed to execute '/ysdisk/ysapps/charhotel/agi-bin/CHAR/checking/checkinout311.php': No such file or directory
Product Model: V4-based S-Series PBX
Firmware Required: 65.X.X.X
Patch and Usage
Download patch here and upload it to app center in pbx.