Personal hotspot keeps searching

Ipad 2 with IOS 6.1.2 the personal hotspot feature does not function. GSM carrier side is ok and the connection sharing is not forbidden, but in Ipad the personal hotspot feature just keeps searching. Have upgraded the IOS to latest one, reset networks etc several times. Nothing seems to help so far. Any ideas how to fix this bug (hope it is not a new feature of IPad 2)?