Sanofi spent $1.5 billion and 20 years to develop its first-of-a-kind dengue vaccine Dengvaxia, but now its promotional efforts for the shot are hitting a wall in the Philippines.

The Philippine FDA has ordered the drug giant to stop advertising for dengue vaccination, pointing out that the company’s TV and radio ads—as well as promo materials in malls—violate local laws. After the government first issued a cease and desist order on Dec. 13, the company continued with the ads at least until Dec. 15, according to the Philippine FDA.

Now, authorities are asking the company to show "why they should not be penalized for violating the law," according to FDA Director General Nela Charade G. Puno.

To further enforce the issue, the government reached out to TV and radio stations telling them not to air the Dengvaxia promotions. The Philippine FDA now says it’ll monitor the situation.

Sanofi has stopped the advertising and has requested a meeting with the FDA to discuss the "legal basis for this apparent decision reversal," according to a spokesperson. The regulator's move "comes as a complete surprise to the company which was in continuous contact with the FDA to ensure compliance of this campaign before its launch in the Philippines on 4th November." Sanofi filed its response on Dec. 27.

The pharma can't further discuss the case as it's now "pending before the FDA."

For Sanofi, the tense relations over Dengvaxia advertising come in a country that has so far been key to its vaccine’s launch. The Philippines, where dengue is endemic, was one of the first countries to approve the vaccine and in April 2016 became the first to implement a large-scale vaccination campaign.

But in the months since Sanofi started shipping doses to the Philippines, the launch has slowed. Execs initially discussed expectations of €200 million for 2016 sales, but in the first three quarters of the year, Sanofi reported €50 million in Dengvaxia sales. Political and economic turmoil in Latin America caught some blame in the second quarter, when the vaccine posted only €1 million in sales.

Sanofi spent $1.5 billion and 20 years developing the vaccine and is implementing a new strategy of "flipping the model" by launching the vaccine in endemic nations first rather than in the U.S. and Europe.