Hennes & Mauritz AB blamed poor weather for flat second-quarter revenue as the Swedish retailer keeps lagging competitor Zara in popularity among fast-fashion shoppers.

Unfavorable weather conditions including a cold March weighed on sales, H&M said, adding that June has got off to a good start. Revenue of 57.62 billion kronor ($5.4 billion) in the three months through May came short of analysts’ estimates.

The slowdown threatens to worsen an inventory buildup that has plagued the retailer for more than six years, and it casts doubt on Chief Executive Officer Helena Helmersson’s goal to double sales by 2030.

Inditex SA, the owner of the Zara chain, reported a 15% rise in revenue for the three months through April, and similar momentum so far this quarter.

Read more: Inditex Surges as Zara Shoppers Buy More in Bigger Stores

Over the weekend, an investigative report in Swedish newspaper Aftonbladet alleged the company’s clothing-recycling program has dumped unwanted garments in countries such as Ghana, which is struggling with clothing waste. H&M has denied the allegations.

(Updates with Aftonbladet report in sixth paragraph)