The Telecom Dispute Settlement Appellate Tribunal (TDSAT) today allowed Tata Teleservices to continue with the advertisement for its fixed wireless service 'walky', which trai had termed as `misleading' and asked the operator to withdraw.Tdsat, however, asked Trai to issue a show-cause notice to the company for 'walky', which has been advertised as 'freedom of mobility at landline rates'. The regulator had asked the company to withdraw the advertisement by today. Meanwhile, Trai has withdrawn the case against the Tatas over the advertisement.During the hearing, Trai argued that positioning a fixed wireless phone as mobile phone was misleading and there was a separate treatment for different calls.Tata Teleservices said there had been no notice from Trai and there was nothing 'misleading' in its advertisement.Tatas have invested Rs 16-18 crore in building the brand name 'walky' and by asking them to withdraw the said advertisement, when there is no offensive in it, would hurt the company, it said.Last week, Trai had asked Tata and Reliance Infocomm to withdraw their fixed wireless ads -- `walky' and `unlimited wireless'.The interconnect usage charges (IUC) and access deficit charge (ADC) regimes provide different treatment for calls from mobile and fixed line, including wireless fixed, and such corrections shall also be made in the relevant content on the website of the operators concerned, Trai had said.